No. Regulations are a popular, and often effective, way of implementing a plan, but they are by no means the only way. Non-regulatory tools, as they are often called, may include setting town priorities for spending funds on improvements, seeking grants to assist in economic development or the design or creation of facilities (be they infrastructure or bike paths), raising awareness of important issues and assistance to residents (for example, affordable housing), promoting desired types of development, setting up annual community events, or preparing local information brochures.
Of course, a plan can also lay the foundation for adopting regulations, including subdivision regulations, flood hazard regulations, wireless telecommunications facilities ordinances, or zoning, among others.