(introduction...)

Many of the least developed countries who began to carry out reform of their instructional programmes as of the seventies were primarily concerned with obtaining school books adapted to the new curricula. But, whilst the reform of programmes requires time and a lot of qualified personnel, it does involve much fewer financial, material and technical resources than does the production of a book. For that reason, many countries have not yet been able to supply schools with all the textbooks required to meet the needs of education. Nevertheless, the existence of renewed and tested curricula considerably facilitates the elaboration of textbooks well adapted to these needs.

In countries already having a solid tradition and long experience of large-scale use of a wide variety of textbooks, competition exists between authors and publishers which offers teachers the possibility to choose those school books they consider most apt. Such is not the case for many countries who are often limited to one single textbook for each discipline at each level of schooling. It is therefore essential that the books produced are of the highest possible quality.

Textbooks are an instructional aid in the teaching-learning process and must correspond to curricula so far as objectives, content and methodology of instruction of each subject are concerned. A textbook usually corresponds to the syllabus of a discipline, the objectives of which can serve as titles or sub-titles of different chapters of the book. In some cases the outline of the textbook is based on these objectives, but the titles of chapters or sub-chapters do not necessarily correspond to the content of the discipline as it stands in the curriculum. The content of the book is, in any case, much richer, in order to provide the quantity of information, explanation, and comment needed to go deeper into the discipline.