One hundred and eighteen project team leaders from five industrial research and development (R&D) organizations were studied to determine the individual characteristics that longitudinally predict leader effectiveness. Hypotheses generated from an interactionist framework and the theory of purposeful work behavior (Barrick et al., ) found an innovative orientation and job involvement to each predict 1‐year later and 5‐years later job performance ratings by immediate supervisors. Low need for clarity predicted 1‐year later performance ratings. Self‐esteem and job involvement each predicted 5‐years later profitability of the project, and job involvement predicted project speed to market. As hypothesized, type of R&D work was found to be a moderator whereby an innovative orientation predicted 1‐year and 5‐years later job performance primarily for research projects, and a low need for clarity predicted 1‐year later performance mainly for research projects. Implications for models of interactionism and leader effectiveness in R&D are discussed.