The results of an empirical comparison between two methods of computer programming are presented, both of which are based on principles of structured programming. Their principal difference is in the approach proposed for problem solving. One approach is prospective: by which the program structure is derived from the data structure. The other is retrospective: one must, on the contrary start from the structure of the results. A relatively complex management program produced by students trained to each of the methods (29 and 17 subjects, respectively) was analysed. Three main results were observed: (a) the type of approach has quite a clear effect on the global program structure and (b) on certain categories of errors, (c) the adoption of a prospective approach (regardless of the method learned) to construct a difficult component of the program. We conclude by a recommendation for the conception of programming methods.