To assure a pool of professional public sector managers, the minimum number of participants was set at 25 senior public sector managers from a population of city managers, deputy city managers and public works directors who were active members of the International City Managers Association (ICMA) and were employed by cities across the United States with a population between 75,000 and 300,000. This group contained approximately 3,000 senior managers. Participation from the private sector was set at a minimum of 15 senior managers from a population of president, executive vice-president, vice presidents of operations, strategic planning or marketing of companies doing a minimum of $50,000,000 per year within the public-private partnership segment of the water industry. This group had an estimated population of 300 senior managers. All participants were then selected at random from within the pre-qualified populations.