The degree of formalization of collection development(the dependent variable) in selected medium-sized academic libraries and six independent variables believed to be related to the dependent variable were examined. The formalization of collection development was measured by an index of five dimensions. The six independent variables examined were age of the library, number of graduate degrees offered by the parent institution, estimated years of growth potential in terms of available shelf space, attitude of the library director toward cooperation, number of memberships held by the library in cooperative endeavors, and percentage of increase in the materials budget, from 1972 to 1982. The findings of this study fail to support hypotheses one, three, four, and six. The relationship between the number of memberships in cooperative endeavors (hypothesis five) is weak, but significant. Hypothesis two is not supported when the total group is considered, but it is supported only when publicly-supported libraries are considered. A positive relationship between size of collection and level of collection development formalization was found to be significant, as was the relationship between number of graduate degrees and size of collection.