BEFORE YOU BEGIN It's considered bad practice (and may result in your map being disapproved) not to have permission of the original author of the custom props/map and use these in your own map.In this example I am extracting the custom models out of 'de_forest.bsp' 1.) Download a a program called Map Analyst (there's a direct link to the file) 2.) Unzip the program, and run the .exe called 'man' 4.) Now that we're in the Map Analyst program, select 'File', then 'Read and Scan BSP' (as shown in the picture below) 5.) Now browse to Program Files/Steam/SteamApps/accountname/counter-strike source/cstrike/maps and click on de_forest.bsp (or whichever .bsp you wish to extract models out of, and assuming this is where you have the .bsp file) and click 'Open' 6.) Now you should see some dialogue appear in the white space in the Map Analyst program. Now go to 'File', 'Export' and then 'Custom Data' (as shown in the picture below) 7.) Now browse to wherever you want the content of the map to be extracted (just extract it to My Documents, and make the file name 'content.zip' 8.) Now, unzip the 'content' folder into your 'Program Files/Steam/SteamApps/common/counter-strike source/cstrike/' directory. This will add all the maps embedded custom content into your CS:S model/sound etc folders. [Alternatively for step 8, pick which custom models/materials of the map you want to use in Hammer (for de\_forest tree models, this would be the 'models' and 'materials' folders in the 'content.zip' you exported) and extract these files into the 'cstrike' directory.] 9.) Restart Hammer if you had it running. To use these models in Hammer using de\_forest as an example, go the model browser in Hammer and filter by 'pine' and the custom de\_forest tree models will pop up for you. NB.) Remember that after you compile the map with the custom tree models, use Pakrat and embed all the custom props back into the .bsp before you release your map to the public.