The work of the INterindustry FORecasting at the University of Maryland (INFORUM) has gradually expanded and similar work is now underway at over fifteen institutes around the world. SLIMFORP, the basic computer programming system for the forecasting models of INFORUM, makes the modeling efforts of the many institutes a practical reality. 

A strong attempt has been made to make the programs portable. The solutions to several problems encountered while transporting the programs from computer to computer now lay hidden in the code. Since unit numbers for specific data files may not be possible on all machines, I wish to call your specific attention to Appendix 2 where the linkage between data files and unit numbers is presented especially well. 

The guide has the strength that it was not written by the original programmer of the model but rather by one, like many of you, who had to implement the model and adapt it to another machine. Thus, I believe, more of the questions asked by the newcomers to the programs are answered and probably in a better way than if I had written this manual.