This paper presents a new multivariate index for use in educational planning. This new index, is called a propinquity index. An individual's propinquity index with respect to a given occupational group is his geometric distance in n-dimensional space from the group centroid, where each dimension is the standard score on one of the original variables weighted by a value representing, at least approximately, the relevance of the corresponding variable in identifying group members. The propinquity index may be used in two ways in helping the individual develop his educational and vocational plans. Converted to a propinquile, it can constitute one of many separate items of information used in arriving at important decisions. In many circumstances the propinquity index may function better as one of the predictors in a multiple regression equation to predict a dichotomous group membership criterion. (Author/KJ)