This paper investigates factors influencing the outcome of union organizing efforts among clerical workers in the private sector. Drawing on interviews with union officials involved in clerical organizing campaigns, the authors analyze NLRB data on elections held in 1979. They find that the percentage of clerical workers voting yes in representation elections was related positively to the strength of the union presence in the state and employment growth in the industry, and negatively to the level of strike activity in the state and management resistance to unionization. The delay between the filing of an election petition and the holding of the election had no significant effect on the vote.