This is an introductory course in mathematics for economists. The goal is familiarizing the students with a set of fundamental mathematical tools that are frequently used in economic modelling. This course is designed with the main purpose of giving students a systematic grounding in Mathematics as an essential instrument for them to use economic models in their own research. The basic concepts about Linear Algebra and Mathematical Analysis that are included in most undergraduate syllabuses are reviewed. Then the course covers some topics in Optimization theory, differential and difference equations. The course is practical, but a systematic review of the most important theoretical concepts is also stressed.