diff --git a/Makefile b/Makefile
index 71ecf5b..6c94108 100644
--- a/Makefile
+++ b/Makefile
@@ -118,7 +118,8 @@ run: build_system
 
 debug: build_system
 	@echo -e ${CL2}[$@] ${CL}executing...${CL3}
-	@gdb $(BINDIR)/gem-graph-server
+	@gdb --args $(BINDIR)/gem-graph-server -C data/config -M data/models \
+		-U data/users
 	@echo -e ${CL2}[$@] ${CL}done.${CL3}
 
 valgrind: build_system
diff --git a/include/arrows.h b/include/arrows.h
index 9096a92..4d70404 100644
--- a/include/arrows.h
+++ b/include/arrows.h
@@ -36,4 +36,29 @@ struct arrow_t {
     uint x;
     uint y;
     uint z;
+
+    struct arrow_t *next;
+    struct arrow_t *prev;
 };
+
+struct condition_t {
+    uint id;
+    uint load;
+    uint site;
+    uint x;
+    uint y;
+    uint z;
+
+    struct condition_t *child;
+    struct condition_t *parent;
+};
+
+/* -------------------------------------------------------------------------- */
+
+struct arrow_t *arrow_new(struct arrow_t *self);
+
+struct arrow_t *arrow_destroy(struct arrow_t *self);
+
+struct condition_t *condition_new(struct condition_t *self);
+
+struct condition_t *condition_destroy(struct condition_t *self);
diff --git a/include/model.h b/include/model.h
index 1056233..1891e3a 100644
--- a/include/model.h
+++ b/include/model.h
@@ -81,6 +81,7 @@ struct state_t
     time_t date;
 
     struct space_t *space;
+    struct arrow_t *arrows;
 };
 
 struct model_t
@@ -115,6 +116,9 @@ struct model_t
     // Handler to the current space of the model
     struct space_t *space;
 
+    // Handler to the conditions
+    struct condition_t *conditions;
+
     // Handler to the arrows
     struct arrow_t *arrows;
     size_t n_arrows;
@@ -122,13 +126,9 @@ struct model_t
     // Handler to the saved states array
     struct state_t *states;
     size_t n_states;
-};
 
-
-struct model_array_t
-{
-    struct model_t *models;
-    size_t size;
+    struct model_t *next;
+    struct model_t *prev;
 };
 
 // -------------------------------------------------------------------------- //
@@ -139,7 +139,7 @@ void model_system_init (struct parameters_t *parameters);
 // -------------------------------------------------------------------------- //
 // Model stopping function                                                    //
 // -------------------------------------------------------------------------- //
-// void model_system_shutdown (void);
+void model_system_shutdown (void);
 
 // -------------------------------------------------------------------------- //
 // Load a model ready to execute                                              //
diff --git a/src/arrows.c b/src/arrows.c
index 79f8f7f..3fa91ff 100644
--- a/src/arrows.c
+++ b/src/arrows.c
@@ -25,3 +25,67 @@
 
 /* -------------------------------------------------------------------------- */
 
+struct arrow_t *arrow_new(struct arrow_t *self)
+{
+    if (self == NULL) {
+        return calloc (1, sizeof(struct arrow_t));
+    }
+
+    self->next = calloc (1, sizeof(struct arrow_t));
+    self->next->prev = self;
+
+    return self->next;
+}
+
+struct arrow_t *arrow_destroy(struct arrow_t *self)
+{
+    struct arrow_t *res = NULL;
+
+    if (self->next)
+        if (self->prev) {
+            self->prev->next = self->next;
+        } else {
+            res = self->next;
+            self->next->prev = NULL;
+        }
+
+    if (self->prev)
+        if (self->next) {
+            self->next->prev = self->prev;
+        } else {
+            res = self->prev;
+            self->prev->next = NULL;
+        }
+
+    free(self);
+
+    return res;
+}
+
+struct condition_t *condition_new(struct condition_t *self)
+{
+    if (self == NULL) {
+        return calloc (1, sizeof(struct condition_t));
+    }
+
+    self->child = calloc (1, sizeof(struct condition_t));
+    self->child->parent = self;
+
+    return self->child;
+}
+
+struct condition_t *condition_destroy(struct condition_t *self)
+{
+    struct condition_t *res = NULL;
+
+    if (self->child) {
+        condition_destroy(self->child);
+    }
+
+    if (self->parent)
+        self->parent->child = NULL;
+
+    free(self);
+
+    return res;
+}
diff --git a/src/main.c b/src/main.c
index 05743ea..cef1e09 100644
--- a/src/main.c
+++ b/src/main.c
@@ -137,6 +137,8 @@ int main(int argc, char **argv)
         returnValue = sched_start (&scheduler, &parameters);
     }
 
+    model_system_shutdown();
+
     free(parameters.userDir);
     free(parameters.modelDir);
     free(parameters.configDir);
diff --git a/src/model.c b/src/model.c
index b631363..09b96ea 100644
--- a/src/model.c
+++ b/src/model.c
@@ -24,6 +24,7 @@
 #include "../include/model.h"
 #include "../include/arrows.h"
 
+#define ALLOWED_RADIUS 10
 #define READ_SITE 1 << 0
 #define READ_WEIGHT 1 << 1
 #define READ_X 1 << 2
@@ -35,70 +36,11 @@
 
 /* -------------------------------------------------------------------------- */
 
-struct model_array_t *knownModels;
+struct model_t *knownModels = NULL;
 
 /* -------------------------------------------------------------------------- */
 
-static bool model_init(struct model_t *self)
-{
-    xmlNode *node;
-
-    /*
-     * this initialize the library and check potential ABI mismatches
-     * between the version it was compiled for and the actual shared
-     * library used.
-     */
-    LIBXML_TEST_VERSION
-
-	self->doc = xmlReadFile(self->filename, NULL, 0);
-
-	if (self->doc == NULL ) {
-        printerr("Error trying to open the XML model !\n");
-		return false;
-	}
-
-	node = xmlDocGetRootElement(self->doc);
-
-	if (node == NULL) {
-		printerr("Empty XML model !\n");
-		xmlFreeDoc(self->doc);
-		return false;
-	}
-
-	if (xmlStrcmp(node->name, (xmlChar *) "gem-graph-model")) {
-		printerr("document of the wrong type, root node != gem-graph-model\n");
-		xmlFreeDoc(self->doc);
-		return false;
-	}
-
-    self->hashtable = xmlHashCreate(0);
-
-    if (self->hashtable == NULL) {
-		printerr("Can't create model hash table !\n");
-		xmlFreeDoc(self->doc);
-		return false;
-    }
-
-    return true;
-}
-
-static bool model_shutdown(struct model_t *self)
-{
-    xmlFreeDoc(self->doc);
-    xmlHashFree(self->hashtable, NULL);
-
-    // Cleanup function for the XML library
-    xmlCleanupParser();
-
-    // This is to debug memory for regression tests
-    xmlMemoryDump();
-
-    return true;
-}
-
-/* -------------------------------------------------------------------------- */
-
-static inline xmlNodePtr getNextChild(xmlNodePtr node, xmlChar *last)
+static inline xmlNodePtr getNextChild (xmlNodePtr node, xmlChar *last)
 {
     while (node != NULL && xmlStrcmp(node->name, last)) {
         // //printf("   <>--- line n°%lu   <%s>\n", xmlGetLineNo(node), node->name);
@@ -107,14 +49,14 @@ static inline xmlNodePtr getNextChild(xmlNodePtr node, xmlChar *last)
     return node;
 }
 
-static inline xmlChar* splitStrAtSlash(xmlChar *toSplit)
+static inline xmlChar* splitStrAtSlash (xmlChar *toSplit)
 {
     toSplit = (xmlChar *)xmlStrchr(toSplit, '/');
     toSplit = xmlStrsub (toSplit, 1, xmlStrlen(toSplit));
     return toSplit;
 }
 
-static inline xmlChar* getFirstTag(xmlChar *path)
+static inline xmlChar* getFirstTag (xmlChar *path)
 {
     xmlChar *preop = path;
     path = (xmlChar *)xmlStrchr(path, '/');
@@ -123,10 +65,10 @@ static inline xmlChar* getFirstTag(xmlChar *path)
     return  xmlStrsub (preop, 0, xmlStrlen(preop) - xmlStrlen(path) - 1);
 }
 
-static inline xmlChar* getLastTag(xmlChar *path)
+static inline xmlChar* getLastTag (xmlChar *path)
 {
     while ((ulong)xmlStrchr (path, '/'))
-        path = splitStrAtSlash((xmlChar *)path);
+        path = splitStrAtSlash ((xmlChar *)path);
 
     // //printf("last tag in the path = <%s>\n", path);
     return path; // which is no more the given path but only its last tag !
@@ -134,7 +76,7 @@ static inline xmlChar* getLastTag(xmlChar *path)
 
 /* -------------------------------------------------------------------------- */
 
-static xmlNodePtr model_get_node(struct model_t *self, xmlChar *path)
+static xmlNodePtr model_get_node (struct model_t *self, xmlChar *path)
 {
     xmlNodePtr node;
     xmlChar *extrait;
@@ -179,7 +121,7 @@ static xmlNodePtr model_get_node(struct model_t *self, xmlChar *path)
 
 /* -------------------------------------------------------------------------- */
 
-static inline long model_get_node_long_attrib(xmlNodePtr node, char *id)
+static inline long model_get_node_long_attrib (xmlNodePtr node, char *id)
 {
     xmlAttr *attribute;
     xmlChar* value;
@@ -200,7 +142,7 @@ static inline long model_get_node_long_attrib(xmlNodePtr node, char *id)
     return 0;
 }
 
-static inline bool model_get_node_str_attrib(xmlNodePtr node,
+static inline bool model_get_node_str_attrib (xmlNodePtr node,
                                              char *id,
                                              char *dest)
 {
@@ -224,7 +166,7 @@ static inline bool model_get_node_str_attrib(xmlNodePtr node,
 
 /* -------------------------------------------------------------------------- */
 
-char model_get_dim(struct model_t *self)
+char model_get_dim (struct model_t *self)
 {
     xmlAttr *attribute;
     xmlChar* value;
@@ -237,7 +179,7 @@ char model_get_dim(struct model_t *self)
     return 0;
 }
 
-long model_get_dim_value(struct model_t *self, const char *axis)
+long model_get_dim_value (struct model_t *self, const char *axis)
 {
     xmlAttr *attribute;
     xmlChar *value;
@@ -248,7 +190,7 @@ long model_get_dim_value(struct model_t *self, const char *axis)
     return model_get_node_long_attrib(node, axis);
 }
 
-char model_get_multiplicity(struct model_t *self)
+char model_get_multiplicity (struct model_t *self)
 {
     xmlAttr *attribute;
     xmlChar* value;
@@ -262,7 +204,7 @@ char model_get_multiplicity(struct model_t *self)
     return 0;
 }
 
-bool model_get_next_state(struct model_t *self, char *new_state_id)
+bool model_get_next_state (struct model_t *self, char *new_state_id)
 {
     static xmlNodePtr cur_node = NULL;
     xmlAttr *attribute;
@@ -288,7 +230,7 @@ bool model_get_next_state(struct model_t *self, char *new_state_id)
     return false;
 }
 
-long model_get_state_arrows_count(struct model_t *self, const char *state_id)
+long model_get_state_arrows_count (struct model_t *self, const char *state_id)
 {
     xmlNodePtr cur_node = NULL;
     xmlAttr *attribute;
@@ -339,7 +281,7 @@ long model_get_state_arrows_count(struct model_t *self, const char *state_id)
     return value;
 }
 
-bool model_get_next_arrow(struct model_t *self,
+bool model_get_next_arrow (struct model_t *self,
                           struct arrow_t *new_arrow,
                           const char *state_id,
                           char dimension)
@@ -473,11 +415,232 @@ bool model_get_next_arrow(struct model_t *self,
     return false;
 }
 
+bool model_get_next_conditions (struct model_t *self, char *new_cond_id)
+{
+    static xmlNodePtr cur_node = NULL;
+    xmlAttr *attribute;
+    xmlChar *value;
+
+    if (cur_node == NULL) {
+        // Get first state
+        cur_node = model_get_node(self, (xmlChar *)"conditions");
+
+    } else {
+        // Get next state
+        if (cur_node->next)
+            cur_node = cur_node->next;
+        else
+            return false;
+    }
+
+    // Lookup in properties
+    if (model_get_node_str_attrib(cur_node, "id", new_cond_id))
+        return true;
+
+    cur_node = NULL;
+    return false;
+}
+
+bool model_get_next_condition (struct model_t *self,
+                               struct condition_t *new_condition,
+                               const char *cond_id,
+                               char dimension)
+{
+    static xmlNodePtr cur_node = NULL;
+    xmlAttr *attribute;
+    xmlChar *value;
+    bool found = false;
+    char temp_char[25];
+    uint check = 0; // bit field checker
+
+    //printf("NEW CALL : cur_node = %p\n", cur_node);
+
+    assert(new_condition);
+    assert(cond_id);
+
+    if (cur_node == NULL) {
+        // Get first state node
+        cur_node = model_get_node(self, (xmlChar *)"conditions");
+
+        // Lookup in properties
+        while (cur_node && cur_node->properties) {
+            attribute = cur_node->properties;
+
+            // Look for the id attribute
+            if (model_get_node_str_attrib(cur_node, "id", &temp_char)) {
+                if (!xmlStrcmp(temp_char, (const xmlChar *)cond_id)) {
+                    found = true;
+                    break;
+                }
+            }
+            cur_node = cur_node->next;
+        }
+
+        // Check if the state has been found
+        if (!found) {
+            cur_node = NULL;
+            return false;
+        }
+
+        // Get first arrow
+        if (cur_node->children) {
+            cur_node = cur_node->children;
+
+            found = false;
+            while (cur_node && cur_node->name) {
+                if (!xmlStrcmp(cur_node->name, (const xmlChar *)"arrow")) {
+                    found = true;
+                    break;
+                }
+                cur_node = cur_node->next;
+            }
+        }
+
+        // Check if the state has been found
+        if (!found) {
+            cur_node = NULL;
+            return false;
+        }
+
+    } else {
+        // Get next condition
+        found = false;
+        while (cur_node->next) {
+            cur_node = cur_node->next;
+            if (!xmlStrcmp(cur_node->name, (const xmlChar *)"arrow")) {
+                found = true;
+                break;
+            }
+        }
+
+        // Check if the state has been found
+        if (!found) {
+            cur_node = NULL;
+            return false;
+        }
+    }
+
+    //printf("DURING CALL : cur_node = %p\n", cur_node);
+    //printf("DURING CALL : cur_node->name = %s\n", cur_node->name);
+
+    // Lookup in properties
+    if (cur_node && cur_node->properties) {
+        attribute = cur_node->properties;
+
+        while(attribute && attribute->name && attribute->children) {
+            //printf("attr name : %s\n", attribute->name);
+            if (!xmlStrcmp(attribute->name, (const xmlChar *)"site")) {
+                value = xmlNodeListGetString(cur_node->doc, attribute->children, 1);
+                new_condition->site = strtol((char *)value, NULL, 0);
+                xmlFree(value);
+                check |= READ_SITE;
+            }
+            if (!xmlStrcmp(attribute->name, (const xmlChar *)"weight")) {
+                value = xmlNodeListGetString(cur_node->doc, attribute->children, 1);
+                new_condition->load = strtol((char *)value, NULL, 0);
+                xmlFree(value);
+                check |= READ_WEIGHT;
+            }
+            if (!xmlStrcmp(attribute->name, (const xmlChar *)"x")) {
+                value = xmlNodeListGetString(cur_node->doc, attribute->children, 1);
+                new_condition->x = strtol((char *)value, NULL, 0);
+                xmlFree(value);
+                check |= READ_X;
+            }
+            if (!xmlStrcmp(attribute->name, (const xmlChar *)"y")) {
+                value = xmlNodeListGetString(cur_node->doc, attribute->children, 1);
+                new_condition->y = strtol((char *)value, NULL, 0);
+                xmlFree(value);
+                check |= READ_Y;
+            }
+            if (!xmlStrcmp(attribute->name, (const xmlChar *)"z")) {
+                value = xmlNodeListGetString(cur_node->doc, attribute->children, 1);
+                new_condition->z = strtol((char *)value, NULL, 0);
+                xmlFree(value);
+                check |= READ_Z;
+            }
+            attribute = attribute->next;
+        }
+
+        switch(dimension) {
+        case 3:
+            return (bool)(check & SUCCESSFUL_READ_ARROW_XYZ);
+        case 2:
+            return (bool)(check & SUCCESSFUL_READ_ARROW_XY);
+        case 1:
+            return (bool)(check & SUCCESSFUL_READ_ARROW_X);
+        }
+    }
+    cur_node = NULL;
+    return false;
+}
+
+/* -------------------------------------------------------------------------- */
+
+static bool model_init(struct model_t *self)
+{
+    xmlNode *node;
+
+    /*
+     * this initialize the library and check potential ABI mismatches
+     * between the version it was compiled for and the actual shared
+     * library used.
+     */
+    LIBXML_TEST_VERSION
+
+	self->doc = xmlReadFile(self->filename, NULL, 0);
+
+	if (self->doc == NULL ) {
+        printerr("Error trying to open the XML model !\n");
+		return false;
+	}
+
+	node = xmlDocGetRootElement(self->doc);
+
+	if (node == NULL) {
+		printerr("Empty XML model !\n");
+		xmlFreeDoc(self->doc);
+		return false;
+	}
+
+	if (xmlStrcmp(node->name, (xmlChar *) "gem-graph-model")) {
+		printerr("document of the wrong type, root node != gem-graph-model\n");
+		xmlFreeDoc(self->doc);
+		return false;
+	}
+
+    self->hashtable = xmlHashCreate(0);
+
+    if (self->hashtable == NULL) {
+		printerr("Can't create model hash table !\n");
+		xmlFreeDoc(self->doc);
+		return false;
+    }
+
+    return true;
+}
+
+static bool model_shutdown(struct model_t *self)
+{
+    xmlFreeDoc(self->doc);
+    xmlHashFree(self->hashtable, NULL);
+    // This is to debug memory for regression tests
+    //xmlMemoryDump();
+
+    return true;
+}
+
 /* -------------------------------------------------------------------------- */
 
 bool model_load (struct model_t *self)
 {
     char state_id[30] = {0};
+    char conditions_id[30] = {0};
+    struct arrow_t *arrow;
+    struct arrow_t *arrow_next;
+    struct arrow_t *arrow_prev;
+    int n_conditions;
+
 
     if (!model_init (self))
         return false;
@@ -528,12 +691,12 @@ bool model_load (struct model_t *self)
     self->multiplicity = model_get_multiplicity(self);
     printlog("Multiplicity : %d\n", self->multiplicity);
 
+    // States and initial state
     if (!model_get_next_state(self, &state_id)) {
         printerr("No valid state to load\n");
         return false;
     }
 
-    // States and initial state
     self->states = calloc (1, sizeof(struct state_t));
     self->n_states = 1;
     memcpy(&self->states[0].id, &state_id, 25);
@@ -542,31 +705,155 @@ bool model_load (struct model_t *self)
     printlog("Initial state : %s\n", &self->states[0].id);
 
     // Initial state arrows
-    self->n_arrows = model_get_state_arrows_count(self, state_id);
-    self->arrows = calloc (self->n_arrows, sizeof(struct arrow_t));
+    self->arrows = arrow_new (self->arrows);
 
-    for (int i = 0; i < self->n_arrows; i++) {
-        model_get_next_arrow(self,
-                             &self->arrows[i],
-                             &self->states[0].id,
-                             self->dimension);
+    if (model_get_next_arrow(self,
+                         self->arrows,
+                         &self->states[0].id,
+                         self->dimension)) {
+        self->n_arrows++;
+
+        while (model_get_next_arrow(self,
+                                    arrow_new (self->arrows),
+                                    &self->states[0].id,
+                                    self->dimension)) {
+            self->n_arrows++;
+        }
     }
 
     printlog("Loaded %d arrows\n", self->n_arrows);
 
+    self->states[0].arrows = self->arrows;
+
+    // Conditions
+    if (!model_get_next_conditions(self, &conditions_id)) {
+        printerr("No valid conditions to load\n");
+        return false;
+    }
+
+    // Loading each condition
+    self->conditions = condition_new (self->conditions);
+
+    if (model_get_next_condition(self,
+                         self->conditions,
+                         &conditions_id,
+                         self->dimension)) {
+        n_conditions = 1;
+        while (model_get_next_arrow(self,
+                                    condition_new (self->conditions),
+                                    &conditions_id,
+                                    self->dimension)) {
+            n_conditions++;
+        }
+    }
+
+    printlog("Loaded %d conditions\n", n_conditions);
+
     return true;
 }
 
+bool model_unload (struct model_t *self)
+{
+    if (!model_shutdown (self))
+        return false;
+
+    if (self->owner_name) {
+        free(self->owner_name);
+        self->owner_name = NULL;
+    }
+    if (self->model_name) {
+        free(self->model_name);
+        self->model_name = NULL;
+    }
+    if (self->space) {
+        if (self->space->units) {
+            free(self->space->units);
+            self->space->units = NULL;
+        }
+        free(self->space);
+        self->space = NULL;
+    }
+    if (self->arrows) {
+        while (self->arrows) {
+            self->arrows = arrow_destroy (self->arrows);
+        }
+    }
+    if (self->states) {
+        free(self->states);
+        self->states = NULL;
+    }
+
+    return true;
+}
+
+struct model_t *model_new(const char *path, const char *basename)
+{
+    struct model_t *self = NULL;
+    struct model_t *prev = NULL;
+
+    // Allocate and insert in the list
+    self = calloc (1, sizeof(struct model_t));
+
+    // We want a cyclic chain
+    // This is the first model
+    if (!knownModels) {
+        knownModels = self;
+        self->next = self;
+        self->prev = self;
+
+    // This is not the first model
+    } else {
+        self->next = knownModels->next;
+        knownModels->next = self;
+        self->prev = knownModels;
+    }
+
+    // Allocate filename with trailing '\0'
+    self->filename =
+        calloc (1, strlen (path)
+                    + sizeof((char)'/')
+                    + strlen (basename)
+                    + sizeof((char)'\0'));
+
+    memcpy (self->filename,
+            path,
+            strlen (path));
+
+    self->filename[
+        strlen (path)] = '/';
+
+    memcpy (self->filename
+                + strlen (path)
+                + sizeof((char)'/'),
+            basename,
+            strlen (basename));
+
+    return self;
+}
+
+void model_destroy(struct model_t *self)
+{
+    if (self->filename) {
+        free(self->filename);
+        self->filename = NULL;
+    }
+
+    if (self->next != self) {
+        self->prev->next = self->next;
+        self->next->prev = self->prev;
+    }
+
+    free(self);
+}
+
 void model_system_init (struct parameters_t *parameters)
 {
     struct dirent *modelDirEntry = NULL;
+    struct model_t *new_model;
     DIR *modelDir = NULL;
     char *extensionPosition;
     int i;
 
-    // Allocate model storage
-    knownModels = calloc (1, sizeof(struct model_array_t));
-
     // Open model directory
     if ((modelDir = opendir (parameters->modelDir)) <= 0) {
         printerr ("Could not open %s\n", parameters->modelDir);
@@ -575,38 +862,40 @@ void model_system_init (struct parameters_t *parameters)
     while ((modelDirEntry = readdir (modelDir)) != NULL) {
         if ((extensionPosition = strstr (modelDirEntry->d_name, ".xml"))) {
 
-            i = knownModels->size;
-
-            // Creating model
-            knownModels->models = reallocarray (knownModels->models,
-                                        ++knownModels->size,
-                                        sizeof(struct model_t));
-
-            // Allocate filename with trailing '\0'
-            knownModels->models[i].filename =
-                calloc (1, strlen (parameters->modelDir)
-                            + sizeof((char)'/')
-                            + strlen (modelDirEntry->d_name)
-                            + sizeof((char)'\0'));
-
-            memcpy (knownModels->models[i].filename,
-                    parameters->modelDir,
-                    strlen (parameters->modelDir));
-
-            knownModels->models[i].filename[
-                strlen (parameters->modelDir)] = '/';
-
-            memcpy (knownModels->models[i].filename
-                        + strlen (parameters->modelDir)
-                        + sizeof((char)'/'),
-                    modelDirEntry->d_name,
-                    strlen (modelDirEntry->d_name));
+            new_model = model_new (parameters->modelDir, modelDirEntry->d_name);
 
             // Ask to parse the new model
-            if (model_load (&knownModels->models[i]))
+            if (model_load (new_model)) {
                 // XXX Check model is valid and/or parsed
-                printlog ("Loaded %s\n", knownModels->models[i].filename);
+                printlog ("Loaded %s\n", new_model->filename);
+            } else {
+                printerr ("Failed to load %s\n", new_model->filename);
+                model_unload (new_model);
+                model_destroy (new_model);
+            }
         }
     }
     free(modelDir);
 }
+
+void model_system_shutdown (void)
+{
+    struct model_t *model = knownModels;
+    struct model_t *next = NULL;
+
+    while ((model != model->next)) {
+        printlog ("Freeing %s\n", model->filename);
+        next = model->next;
+        model_unload(model);
+        model_destroy(model);
+        model = next;
+    }
+
+    if (model) {
+        model_unload (model);
+        model_destroy (model);
+    }
+
+    // Cleanup function for the XML library
+    xmlCleanupParser();
+}
diff --git a/src/scheduler.c b/src/scheduler.c
index d2affad..e16deb6 100644
--- a/src/scheduler.c
+++ b/src/scheduler.c
@@ -98,20 +98,14 @@ static int sched_run(struct scheduler_t *self,
 int sched_start (struct scheduler_t *self, struct parameters_t *parameters)
 {
     int n_threads = omp_get_max_threads();
-    int n_models = 20;
     int returnValue;
+    struct model_t *model;
     self->id = sched_new_id();
 
     printlog("Scheduler %d initialized with %d threads\n",
              self->id,
              n_threads);
 
-    // Allocating models
-    self->models = calloc(n_models, sizeof(struct model_t*));
-    for (int i = 0; i < n_models; i++) {
-        self->models[i] = calloc(1, sizeof(struct model_t));
-        //XXX populate model
-    }
 
     // Allocating workers
     self->workers = calloc(n_threads, sizeof(struct worker_t*));
@@ -119,10 +113,13 @@ int sched_start (struct scheduler_t *self, struct parameters_t *parameters)
         self->workers[i] = calloc(1, sizeof(struct worker_t));
     }
 
-    // Run
-    #pragma omp for
-    for (int i = 0; i < n_models; i++)
-        returnValue = sched_run(self, parameters, self->models[i]);
+    // Retrieve models
+    model = self->models;
+    while(model) {
+        printlog ("Scheduling model %d\n", model->id);
+        returnValue = sched_run(self, parameters, self->models);
+        model = model->next;
+    }
 
     // Freeing workers
     for (int i = 0; i < n_threads; i++) {
@@ -130,11 +127,7 @@ int sched_start (struct scheduler_t *self, struct parameters_t *parameters)
     }
     free(self->workers);
 
-    // Freeing models
-    for (int i = 0; i < n_models; i++) {
-        free(self->models[i]);
-    }
-    free(self->models);
-
     return returnValue;
 }
+
+