diff --git a/game.cpp b/game.cpp
index a8673db..acdd0c3 100644
--- a/game.cpp
+++ b/game.cpp
@@ -125,7 +125,7 @@ void Game::render()
 	}
     }
 
-    // ring the selected vertex and write info about it
+    // highlight the selected vertex and write info about it
     if (data.get_current_vertex() != NULL)
     {
 	GameVertex* v = data.get_current_vertex();
@@ -169,6 +169,8 @@ void Game::render()
 	}
     }
 
+    draw_player_info();
+
     SDL_Flip(display);
 }
 
@@ -218,6 +220,19 @@ void Game::draw_node(GameVertex* v)
 }
 
 
+void Game::draw_player_info()
+{
+    Player* player = data.get_turn();
+
+    DrawUtils::draw_text(display, player->get_name(), 680, display->h - 95,
+			 font);
+
+    string temp = "Energy: ";
+    temp += itos(player->get_energy());
+    DrawUtils::draw_text(display, temp, 680, display->h - 80, font);
+}
+
+
 void Game::handle_button_press(ButtonAction action)
 {
     switch (action)
diff --git a/game.h b/game.h
index bd67e1f..2e00db4 100644
--- a/game.h
+++ b/game.h
@@ -41,6 +41,7 @@ class Game : public GameState
     void draw_stats(GameVertex* v);
     void draw_button(MenuButton* button);
     void draw_node(GameVertex* v);
+    void draw_player_info();
 
     void handle_button_press(ButtonAction action);
 
diff --git a/gamedata.cpp b/gamedata.cpp
index ab9a856..b170161 100644
--- a/gamedata.cpp
+++ b/gamedata.cpp
@@ -67,6 +67,7 @@ void GameData::toggle_turn()
 	{
 	    mode = MODE_SELECT;
 	    build_type = VERTEX_NONE;
+	    produce_energy();
 	}
     }
 
@@ -83,8 +84,6 @@ void GameData::handle_click(int x, int y)
 
     GameVertex* v = dynamic_cast<GameVertex*>(vertex_at(x, y, 0));
 
-    // fixme - energy expenditure should happen in each of these cases except
-    // MODE_SELECT
     switch (mode)
     {
     case MODE_SELECT:
@@ -100,11 +99,15 @@ void GameData::handle_click(int x, int y)
 	break;
     case MODE_MOVE:
 	if (current == NULL) return;
-	if (MathUtils::distance(current->x, current->y, current->z, x, y, 0)
-	    <= get_range())
+	int dist = MathUtils::distance(current->x, current->y, current->z,
+				       x, y, 0);
+	if (dist <= get_range())
 	{
-	    current->x = x;
-	    current->y = y;
+	    if (turn->spend_energy(dist))
+	    {
+		current->x = x;
+		current->y = y;
+	    }
 	}
 	break;
     }
@@ -123,7 +126,21 @@ bool GameData::select_vertex(int x, int y)
 
 bool GameData::add_vertex(int x, int y, int z, int r, int colour)
 {
-    if (build_type == VERTEX_NONE) return false;
+    int energy_cost = 0;
+    switch (build_type)
+    {
+    case VERTEX_NONE:
+	return false;
+    case VERTEX_ATTACKER:
+	energy_cost = 50;
+	break;
+    case VERTEX_DEFENDER:
+	energy_cost = 25;
+	break;
+    case VERTEX_PRODUCER:
+	energy_cost = 25 + (25 * num_vertices_by_type(build_type, turn));
+	break;
+    }
 
     GameVertex* v = new GameVertex(x, y, z, r, colour, 10, build_type, turn);
 
@@ -134,12 +151,15 @@ bool GameData::add_vertex(int x, int y, int z, int r, int colour)
 	{
 	    if (Graph::add_vertex(v))
 	    {
-		toggle_turn();
-		return true;
+		if (turn->spend_energy(energy_cost))
+		{
+		    toggle_turn();
+		    return true;
+		}
+		else remove_vertex(v);
 	    }
 	}
 
-	// really, we shouldn't be able to get here. return false just in case
 	delete v;
 	return false;
     }
@@ -161,6 +181,7 @@ bool GameData::add_vertex(int x, int y, int z, int r, int colour)
 
     if (Graph::add_vertex(v, current))
     {
+	if (!turn->spend_energy(energy_cost)) remove_vertex(v);
 	mode = MODE_SELECT;
 	return true;
     }
@@ -245,3 +266,28 @@ bool GameData::endgame()
 
     return false;
 }
+
+
+int GameData::num_vertices_by_type(VertexType type, Player* player)
+{
+    int num = 0;
+
+    for (list<Vertex*>::iterator cursor = vertices.begin();
+	 cursor != vertices.end(); cursor++)
+    {
+	GameVertex* v = dynamic_cast<GameVertex*>(*cursor);
+
+	if (player != NULL && v->player != player) continue;
+
+	if (v->type == type) num++;
+    }
+
+    return num;
+}
+
+
+void GameData::produce_energy()
+{
+    int amount = 25 * num_vertices_by_type(VERTEX_PRODUCER, turn);
+    turn->add_energy(amount);
+}
diff --git a/gamedata.h b/gamedata.h
index be1f30c..22521cf 100644
--- a/gamedata.h
+++ b/gamedata.h
@@ -44,6 +44,10 @@ class GameData : public Graph
     Player* get_turn() const { return turn; }
 
  private:
+    int num_vertices_by_type(VertexType type, Player* player = NULL);
+    void produce_energy();
+
+
     GameVertex* current;
     Player player1, player2;
     Player* turn;
diff --git a/player.cpp b/player.cpp
index cd13d4c..e6f9812 100644
--- a/player.cpp
+++ b/player.cpp
@@ -4,7 +4,7 @@ Player::Player(string name, unsigned int colour)
 {
     this->name = name;
     this->colour = colour;
-    energy = 50;
+    energy = 25;
 }