Methodological constants in courseware design

The author draws on her practical experience in courseware development as well as her research experience in the development of authoring systems to suggest that, in spite of the significant changes currently taking place in this field, some of the old models proposed for courseware development maintain their validity from a methodological point of view. The paper analyses the common denominator among several models for courseware development (the methodological constants) and discusses in detail both the design and the validation phases.