At the invitation of the UK Environment Agency (EA), the US Environmental Protection Agency (EPA) initiated the Integrated Permitting International Collaboration Effort (IP ICE). The UK EA has been a dedicated partner throughout the effort. The objective of the effort was to study the EU-mandated Integrated Pollution Prevention and Control (IPPC) permitting system as implemented in the UK. In order to carry out the study, a network was created consisting of interested EPA and state environmental agency representatives, as well as a multi-disciplinary research team led by EPA's National Center for Environmental Innovation (NCEI) and including members from EPA headquarters, EPA regional offices, and a state. The research team embarked on a detailed analysis of the UK IPPC permitting system; the report is the product of that effort. In order to accomplish this undertaking, the research team drew on available literature and personal interactions and site visits with EA officials, UK industry representatives, and members of the IP ICE network. In brief, the report introduces the historical and cultural setting for the UK integrated permitting system and provides information regarding the legal and organizational permitting structure and function. In order to understand the UK system, detailed information is offered about the permitting process and permit requirements. In addition, a comparative analysis is provided of several individual permits in the UK and US for the pulp and paper sector and the specialty organic chemical sector. Finally, the report delivers a series of findings regarding features of the UK permitting system that are of particular note to US observers.