diff --git a/ai_build.c b/ai_build.c
new file mode 100644
--- /dev/null
+++ b/ai_build.c
@@ -0,0 +1,257 @@
+#include "stdafx.h"
+#include "ttd.h"
+#include "command.h"
+#include "ai.h"
+#include "engine.h"
+
+// Build HQ
+//  Params:
+//    tile : tile where HQ is going to be build
+bool AiNew_Build_CompanyHQ(Player *p, uint tile) {
+	if (DoCommandByTile(tile, 0, 0, DC_AUTO | DC_NO_WATER, CMD_BUILD_COMPANY_HQ) == CMD_ERROR)
+		return false;
+	DoCommandByTile(tile, 0, 0, DC_EXEC | DC_AUTO | DC_NO_WATER, CMD_BUILD_COMPANY_HQ);
+	return true;
+}
+
+// Build station
+//  Params:
+//    type : AI_TRAIN/AI_BUS/AI_TRUCK : indicates the type of station
+//    tile : tile where station is going to be build
+//    length : in case of AI_TRAIN: length of station
+//    numtracks : in case of AI_TRAIN: tracks of station
+//    direction : the direction of the station
+//    flag : flag passed to DoCommand (normally 0 to get the cost or DC_EXEC to build it)
+int AiNew_Build_Station(Player *p, byte type, uint tile, byte length, byte numtracks, byte direction, byte flag) {
+	if (type == AI_TRAIN)
+		return DoCommandByTile(tile, direction + (numtracks << 8) + (length << 16), 0, flag | DC_AUTO | DC_NO_WATER, CMD_BUILD_RAILROAD_STATION);
+	else if (type == AI_BUS)
+		return DoCommandByTile(tile, direction, 0, flag | DC_AUTO | DC_NO_WATER, CMD_BUILD_BUS_STATION);
+	else
+		return DoCommandByTile(tile, direction, 0, flag | DC_AUTO | DC_NO_WATER, CMD_BUILD_TRUCK_STATION);
+}
+
+// Builds a brdige. The second best out of the ones available for this player
+//  Params:
+//   tile_a : starting point
+//   tile_b : end point
+//   flag : flag passed to DoCommand
+int AiNew_Build_Bridge(Player *p, uint tile_a, uint tile_b, byte flag) {
+	int bridge_type, bridge_len, type, type2;
+
+	// Find a good bridgetype (the best money can buy)
+	bridge_len = GetBridgeLength(tile_a, tile_b);
+	type = type2 = 0;
+	for (bridge_type = MAX_BRIDGES-1; bridge_type >= 0; bridge_type--) {
+		if (CheckBridge_Stuff(bridge_type, bridge_len)) {
+			type2 = type;
+			type = bridge_type;
+			// We found two bridges, exit
+			if (type2 != 0)
+				break;
+		}
+	}
+	// There is only one bridge that can be build..
+	if (type2 == 0 && type != 0) type2 = type;
+
+	// Now, simply, build the bridge!
+	if (p->ainew.tbt == AI_TRAIN)
+		return DoCommandByTile(tile_a, tile_b, (0<<8) + type2, flag | DC_AUTO, CMD_BUILD_BRIDGE);
+	else
+		return DoCommandByTile(tile_a, tile_b, (0x80 << 8) + type2, flag | DC_AUTO, CMD_BUILD_BRIDGE);
+}
+
+
+// Build the route part by part
+// Basicly what this function do, is build that amount of parts of the route
+//  that go in the same direction. It sets 'part' to the last part of the route builded.
+//  The return value is the cost for the builded parts
+//
+//  Params:
+//   PathFinderInfo : Pointer to the PathFinderInfo used for AiPathFinder
+//   part : Which part we need to build
+//
+// TODO: skip already builded road-pieces (e.g.: cityroad)
+int AiNew_Build_RoutePart(Player *p, Ai_PathFinderInfo *PathFinderInfo, byte flag) {
+    int part = PathFinderInfo->position;
+	byte *route_extra = PathFinderInfo->route_extra;
+	TileIndex *route = PathFinderInfo->route;
+	int dir;
+	int old_dir = -1;
+	int cost = 0;
+	int res;
+	// We need to calculate the direction with the parent of the parent.. so we skip
+	//  the first pieces and the last piece
+	if (part < 1) part = 1;
+	// When we are done, stop it
+	if (part >= PathFinderInfo->route_length - 1) { PathFinderInfo->position = -2; return 0; }
+	
+	
+	if (PathFinderInfo->rail_or_road) {
+		// Tunnel code
+     	if ((AI_PATHFINDER_FLAG_TUNNEL & route_extra[part]) != 0) {
+     		cost += DoCommandByTile(route[part], 0, 0, flag, CMD_BUILD_TUNNEL);
+     		PathFinderInfo->position++;
+     		// TODO: problems!
+     		if (cost == CMD_ERROR) {
+     			DEBUG(ai,0)("[AiNew - BuildPath] We have a serious problem: tunnel could not be build!");
+				return 0;
+     		}
+     		return cost;
+     	}
+     	// Bridge code
+     	if ((AI_PATHFINDER_FLAG_BRIDGE & route_extra[part]) != 0) {
+     		cost += AiNew_Build_Bridge(p, route[part], route[part-1], flag);
+     		PathFinderInfo->position++;
+     		// TODO: problems!
+     		if (cost == CMD_ERROR) {
+     			DEBUG(ai,0)("[AiNew - BuildPath] We have a serious problem: bridge could not be build!");
+				return 0;
+     		}
+     		return cost;
+     	}
+
+     	// Build normal rail
+     	// Keep it doing till we go an other way
+     	if (route_extra[part-1] == 0 && route_extra[part] == 0) {
+     		while (route_extra[part] == 0) {
+	     		// Get the current direction
+	     		dir = AiNew_GetRailDirection(route[part-1], route[part], route[part+1]);
+	     		// Is it the same as the last one?
+	     		if (old_dir != -1 && old_dir != dir) break;
+	     		old_dir = dir;
+	     		// Build the tile
+	     		res = DoCommandByTile(route[part], 0, dir, flag, CMD_BUILD_SINGLE_RAIL);
+	     		if (res == CMD_ERROR) {
+	     			// Problem.. let's just abort it all!
+	     			p->ainew.state = AI_STATE_NOTHING;
+	     			return 0;
+	     		}
+	     		cost += res;
+	     		// Go to the next tile
+	     		part++;
+	     		// Check if it is still in range..
+	     		if (part >= PathFinderInfo->route_length - 1) break;
+	     	}
+	     	part--;
+	    }
+     	// We want to return the last position, so we go back one
+     	PathFinderInfo->position = part;
+    } else {
+		// Tunnel code
+     	if ((AI_PATHFINDER_FLAG_TUNNEL & route_extra[part]) != 0) {
+     		cost += DoCommandByTile(route[part], 0x200, 0, flag, CMD_BUILD_TUNNEL);
+     		PathFinderInfo->position++;
+     		// TODO: problems!
+     		if (cost == CMD_ERROR) {
+     			DEBUG(ai,0)("[AiNew - BuildPath] We have a serious problem: tunnel could not be build!");
+				return 0;
+     		}
+     		return cost;
+     	}
+     	// Bridge code
+     	if ((AI_PATHFINDER_FLAG_BRIDGE & route_extra[part]) != 0) {
+     		cost += AiNew_Build_Bridge(p, route[part], route[part+1], flag);
+     		PathFinderInfo->position++;
+     		// TODO: problems!
+     		if (cost == CMD_ERROR) {
+     			DEBUG(ai,0)("[AiNew - BuildPath] We have a serious problem: bridge could not be build!");
+				return 0;
+     		}
+     		return cost;
+     	}
+
+     	// Build normal road
+     	// Keep it doing till we go an other way
+     	// EnsureNoVehicle makes sure we don't build on a tile where a vehicle is. This way
+     	//  it will wait till the vehicle is gone..
+     	if (route_extra[part-1] == 0 && route_extra[part] == 0 && (flag != DC_EXEC || EnsureNoVehicle(route[part]))) {
+     		while (route_extra[part] == 0 && (flag != DC_EXEC || EnsureNoVehicle(route[part]))) {
+	     		// Get the current direction
+	     		dir = AiNew_GetRoadDirection(route[part-1], route[part], route[part+1]);
+	     		// Is it the same as the last one?
+	     		if (old_dir != -1 && old_dir != dir) break;
+	     		old_dir = dir;
+	     		// There is already some road, and it is a bridge.. don't build!!!
+	     		if (!IS_TILETYPE(route[part], MP_TUNNELBRIDGE)) {
+	     			// Build the tile
+	     			res = DoCommandByTile(route[part], dir, 0, flag | DC_NO_WATER, CMD_BUILD_ROAD);
+	     			// Currently, we ignore CMD_ERRORs!
+	     			if (res == CMD_ERROR && !IS_TILETYPE(route[part], MP_STREET) && (flag == DC_EXEC && !EnsureNoVehicle(route[part]))) {
+     					// Problem.. let's just abort it all!
+     					DEBUG(ai,0)("Darn, the route could not be builded.. aborting!");
+    	     			p->ainew.state = AI_STATE_NOTHING;
+    	     			return 0;
+    	     		} else {
+    	     			if (res != CMD_ERROR)
+    	     				cost += res;
+    	     		}
+		     	}
+	     		// Go to the next tile
+	     		part++;
+	     		// Check if it is still in range..
+	     		if (part >= PathFinderInfo->route_length - 1) break;
+	     	}
+	     	part--;
+	     	// We want to return the last position, so we go back one
+	    }
+	    if (!EnsureNoVehicle(route[part]) && flag == DC_EXEC) part--;
+     	PathFinderInfo->position = part;
+    }
+    
+    return cost;
+}
+
+// This functions tries to find the best vehicle for this type of cargo
+// It returns vehicle_id or -1 if not found
+int AiNew_PickVehicle(Player *p) {
+    if (p->ainew.tbt == AI_TRAIN) {
+        // Not supported yet
+        return -1;
+    } else {
+        int start, count, i, r = CMD_ERROR;
+        start = _cargoc.ai_roadveh_start[p->ainew.cargo];
+        count = _cargoc.ai_roadveh_count[p->ainew.cargo];
+
+        // Let's check it backwards.. we simply want to best engine available..
+        for (i=start+count-1;i>=start;i--) {
+        	// Is it availiable?
+        	// Also, check if the reliability of the vehicle is above the AI_VEHICLE_MIN_RELIABILTY
+        	if (!HASBIT(_engines[i].player_avail, _current_player) || _engines[i].reliability * 100 < AI_VEHICLE_MIN_RELIABILTY << 16) continue;
+        	// Can we build it?
+        	r = DoCommandByTile(0, i, 0, DC_QUERY_COST, CMD_BUILD_ROAD_VEH);
+        	if (r != CMD_ERROR) break;
+       	}
+       	// We did not find a vehicle :(
+       	if (r == CMD_ERROR) { return -1; }
+       	return i;
+    }
+}
+
+// Builds the best vehicle possible
+int AiNew_Build_Vehicle(Player *p, uint tile, byte flag) {
+	int i = AiNew_PickVehicle(p);
+	if (i == -1) return CMD_ERROR;
+	
+	if (p->ainew.tbt == AI_TRAIN) {
+		return CMD_ERROR;
+	} else {
+		return DoCommandByTile(tile, i, 0, flag, CMD_BUILD_ROAD_VEH);
+	}
+}
+
+int AiNew_Build_Depot(Player *p, uint tile, byte direction, byte flag) {
+	static const byte _roadbits_by_dir[4] = {2,1,8,4};
+	int r, r2;
+    if (p->ainew.tbt == AI_TRAIN) {
+    	return DoCommandByTile(tile, 0, direction, flag | DC_AUTO | DC_NO_WATER, CMD_BUILD_TRAIN_DEPOT);
+    } else {
+    	r = DoCommandByTile(tile, direction, 0, flag | DC_AUTO | DC_NO_WATER, CMD_BUILD_ROAD_DEPOT);
+    	if (r == CMD_ERROR) return r;
+    	// Try to build the road from the depot
+    	r2 = DoCommandByTile(tile + _tileoffs_by_dir[direction], _roadbits_by_dir[direction], 0, flag | DC_AUTO | DC_NO_WATER, CMD_BUILD_ROAD);
+    	// If it fails, ignore it..
+    	if (r2 == CMD_ERROR) return r;
+    	return r + r2;
+    }
+}