Growth is inevitable in marketing cooperatives operating pools which consistently obtain member returns in excess of cash market prices. In some cooperatives, the capital plan is the only means used to establish a fortuitous membership policy. This article presents a simple conceptual framework for two distinct parts: acquisition and transfer of rights to deliver to a pool, and equality of treatment of new members relative to original members. Specific policy alternatives for each component are defined and examined. The interaction among the components also is considered. The analysis suggests that strategic planning in some cooperatives should involve consideration of alternatives for membership policy.