Beginning in 1992, the Slow The Spread (STS) pilot project was initiated to target gypsy moth (Lymantria dispar L.) spread rate reduction by controlling populations in the transition zone. The project uses intensive monitoring techniques, with pheromone-baited sticky moth traps, to detect low-level populations and target them for eradication. The primary objective of the pilot project was to evaluate the feasibility of using integrated pest management techniques to slow the spread of gypsy moths over a large geographical area. In this study, the cost of STS pilot project activities in 1993–1995 was investigated. A cost accounting system was developed and used as a framework to collect the cost data and to investigate cost patterns and characteristics. Total expenditures of STS activities for 1993–1995 were $7,685.2 million. Per unit cost was $49.67 per trap with the direct cost component being $35.03 per trap. Trapper labor and vehicle expense accounted for ≈90% of this direct cost. Per unit cost for treatment activities was found to average $27.86 per treated acre. In general, the STS pilot project is labor intensive, specifically the trapping component. From 1993–1995, 59% of total project expenditures were spent on trapping activities, 28% on pesticide treatments, and 13% on data management. A trapper productivity rate regression model is described.