Too many people still think that programming, debugging and porting programs to parallel programs is a very tough and almost impossible job. However, with the right tools, programming parallel systems can be almost as simple as programming sequential systems. One of the best environments for programming parallel computers is Express, based on ideas and developments from Caltech, one of the birthplaces of distributed memory machines. Basically, Express is a library of around 100 functions, which perform all the basic tasks of parallel computing: interprocessor communication, accessing hosts, sharing the parallel system, parallel graphics, configuration management, multitasking, performance analysis and debugging. The use of Express makes it possible to port sequential code to a parallel computer and it is extremely easy to port the resulting code to another parallel computer.