This module examines the principles and algorithms for making decisions. It provides a more precise and systematic study of the formal or abstract properties of decision-making scenarios. The module considers decisions of a single individual and situations where the decisions of more than two parties are involved. Topics covered in the first part include: subjective probability, rational preferences and utility, expected utility, risk aversion, objections and alternatives to expected utility theory, and group decisions. The second part provides an introduction to major concepts of game theory.