Quantum field theory is the general framework for our current understanding of elementary particle physics. It is also a much more general language and provides a very useful formalism for solving a number of problems in a variety of subjects. The course aims at both preparing the ground for the study of high energy physics and at providing tools and methods which are useful in a broader area. After attending the course students are supposed to master a few tools (Green function formalism, path integrals) whose capabilities and power they should recognize in a number of problems. Both students involvment in solving problems in front of their collegues and the presentation of the solution they will provide to the final problem they will be assigned are intended as a training of their communication skills (they should be able to argue in public).