Systematic design refers to a process of design that looks not only at the problem that needs to be overcome, but also at the surrounding environment (natural and anthropogenic), and other systems that are linked to the problem. As such, systematic design is the basis for a lot of appropriate technology. Trial and error, and technological evolution are other methods of arriving at a solution appropriate for a system - these are often the basis for vernacular technology. Systematic design, on the other hand, tries to eliminate the time required for these processes, and create a solution in one go. In reality, some combination of approaches is the best - ie. systematic design with prototyping.