diff --git a/src/ai/api/ai_types.hpp b/src/ai/api/ai_types.hpp
new file mode 100644
--- /dev/null
+++ b/src/ai/api/ai_types.hpp
@@ -0,0 +1,40 @@
+/* $Id$ */
+
+/** @file ai_types.hpp Defines all the types of the game, like VehicleID, .... */
+
+#ifndef AI_TYPES_HPP
+#define AI_TYPES_HPP
+
+#include "../../core/overflowsafe_type.hpp"
+#include "../../company_type.h"
+
+/* Define all types here, so we don't have to include the whole _type.h maze */
+typedef uint BridgeType;     //!< Internal name, not of any use for you.
+typedef byte CargoID;        //!< The ID of a cargo.
+class CommandCost;           //!< The cost of a command.
+typedef uint16 EngineID;     //!< The ID of an engine.
+typedef uint16 GroupID;      //!< The ID of a group.
+typedef uint16 IndustryID;   //!< The ID of an industry.
+typedef uint8 IndustryType;  //!< The ID of an industry-type.
+typedef OverflowSafeInt64 Money; //!< Money, stored in a 32bit/64bit safe way. For AIs money is always in pounds.
+typedef uint16 SignID;       //!< The ID of a sign.
+typedef uint16 StationID;    //!< The ID of a station.
+typedef uint16 StringID;     //!< The ID of a string.
+typedef uint32 TileIndex;    //!< The ID of a tile (just named differently).
+typedef uint16 TownID;       //!< The ID of a town.
+typedef uint16 VehicleID;    //!< The ID of a vehicle.
+
+/* Types we defined ourself, as the OpenTTD core doesn't have them (yet) */
+typedef uint AIErrorType;    //!< The types of errors inside the NoAI framework.
+typedef BridgeType BridgeID; //!< The ID of a bridge.
+typedef uint16 SubsidyID;    //!< The ID of a subsidy.
+
+#ifndef _SQUIRREL_H_
+/* Life becomes easier when we can tell about a function it needs the VM, but
+ *  without really including 'squirrel.h'. */
+typedef struct SQVM *HSQUIRRELVM;  //!< Pointer to Squirrel Virtual Machine.
+typedef int SQInteger;             //!< Squirrel Integer.
+typedef struct SQObject HSQOBJECT; //!< Squirrel Object (fake declare)
+#endif
+
+#endif /* AI_TYPES_HPP */