In the United States and Canada, full membership in each country's professional association—American Psychological Association (APA) and Canadian Psychological Association (CPA), respectively—requires doctoral training (except in some Canadian provinces, such as Alberta, where a master's degree is sufficient). The minimal requirement for full membership can be waived in circumstances where there is evidence that significant contribution or performance in the field of psychology has been made. Associate membership requires at least two years of postgraduate studies in psychology or an approved related discipline.