A Performance-Based Road Asset Management and Maintenance Contract or PAMMC is one in which services are provided not on a unit basis (e.g. a fee per pothole filled in a road) but based on an agreed-upon standard that the contractor is to maintain (e.g. all potholes bigger than 75 mm x 100 mm must be filled within a certain length of time) in order to collect the full fee.
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Performance-based road asset management and maintenance contract Wikipedia(Text) CC BY-SA