Yes - you have to set up Hammer for use with Team Fortress 2 Classic. Unlike regular TF2, there isn't a hammer.exe in the tf2classic/bin directory. Instead, we use the hammer.exe within the Source SDK Base 2013 Multiplayer's files. First, navigate to "steam/steamapps/common/Source SDK Base 2013 Multiplayer/bin", find "hammer.exe" and open it. Next, go to Tools > Options In the window which opens, click the edit button next to the Configuration dropdown. In the following window which pops up, click add and set the name as "Team Fortress 2 Classic". Close the Edit Game Configurations window and hit "Add" next to the game data files section. Navigate to your TF2C folder in "steam/steamapps/sourcemods" and select <span style="font-weight: bold;">tf2c.fgd.</span> Now under <span style="font-weight: bold;">Game Executable Directory click browse and set the directory to the SDK Base 2013 Multiplayer folder. Set the Game Directory to your tf2classic folder and your Hammer VMF Directory to tf2classic/maps. You can set the Hammer VMF Directory to wherever you'd like, but I have it set to the tf2classic/maps folder.</span> Now switch to the Build Programs tab at the top, make sure Team Fortress 2 Classic is selected in the configuration dropdown, and then set the Game Executable to "hl2.exe" which can be found in the SDK Base 2013 Multiplayer root folder. Set each of the BSP, VIS and RAD executables to "vbsp.exe", "vvis.exe" and "vrad.exe" respectively. These executables can be found in the /bin folder of the SDK Base 2013 Multiplayer folder. Now set the "place compiled maps in this directory before running the game" directory to your tf2classic/maps folder. You can now hit OK and should probably restart Hammer just to be sure everything's settled. Now you should be set up to start mapping. If you have any questions please post them here.