This manual is aimed at students in the fourth year of secondary school, in the Economics and Management section. We have produced it in accordance with the new curriculum (applicable from September 2022).this manual has a unifying concept: it is a continuum whose different parts refer to each other. It is not intended to be exhaustive, but rather pedagogical and explanatory, so as to make the essential clear and open up a wider field. Our main objectives are: - to consolidate the knowledge already acquired in 2nd and 3rd year;- to motivate students by enabling them to apply their knowledge in concrete situations;- to help students understand the value and limits of the information available for decision-making. In writing this manual, we have done our utmost to produce a pleasant and attractive work that will enable students to approach their end-of-year exams in excellent conditions. Finally, we’d be delighted to receive any constructive criticism and suggestions from our colleagues who would like to see the manual improved