This study identifies major problems and concerns encountered when attempting to apply the multifaceted classification model developed by Campbell and others (1981) called "Patterns of Participation," which describes the multiple ways that secondary students participate in vocational education and how their courses are classified. It also assesses how well the outcomes of those applications replicated or verified selected empirical results reported by the model's developers. The model was applied to the high school transcripts of samples of students from three urban school districts. Two major conclusions were reached. The first conclusion is that while no debilitating problems were encountered during the applications of the model, a number of conceptual and operational concerns were identified. These concerns include the following: (1) Local school districts often use unique course titles that do not correspond directly with those listed in the codebook of the model; (2) local districts define and offer more general courses than those cited in the codebook; (3) some courses do not fit into the model's definitions; (4) some definitions and rules of the model need clarification; and (5) certain vocational programs are "discriminated" against by the model. The second conclusion was that the model is replicable across data sets and should, therefore, be of use to vocational planners and researchers. (KC)