Formal planning can yield many benefits for all types of companies but many companies are experiencing difficulties with marketing planning. It has been recognized that expert systems would bring benefits to companies by helping them make better strategic plans, but the development of expert marketing systems is difficult and time consuming. Discusses some important issues related to the development of expert marketing systems. These issues are associated with understanding the domain, identifying users’ problems, knowing the limitation of expert systems and designing user‐friendly interface. These issues seem to have not been addressed adequately from expert system developers. It is hoped that discussions herein would help others to understand these issues better and to develop more successful expert marketing systems.