This paper highlights the importance of understanding coordination problems for the study of collective action. To this end, the paper consists of three parts. First, the main difference between cooperation and coordination problems are displayed. Second, the structure of a coordination problem is analysed, specially the relationship between coordination situations and the generation of common knowledge. Thirdly, the most recurrent solutions to coordination problems are described, namely: agreements, salience and learning. After considering these solutions, the paper speculates about other possible ways of interpreting how people solve coordination problems.