Abstract: Selected resources that satisfy a specified technical requirement are entered into a selected pool as a function of a sourcing rate, a screening rate and a selection rate that are each variable over time and applied during a sequence of selection time periods that span a demand forecast time period. Offers for acquisition are iteratively made to the selected pool of resources in a sequence of different offer time periods, wherein the resources are progressively moved into different awaiting offer buffers after each of the offer time periods. The demand number is re-forecast and one or more of the sourcing, screening and selection rates adjusted to minimize a combination of costs of the rates with a cost of acquiring resources to satisfy the gap number as a function of the demand number.