Central concepts The theoretical foundation of geographic profiling is in environmental criminology. Key concepts include: Journey-to-Crime Supports the notion that crimes are likely to occur closer to an offender’s home and follow a distance-decay function (DDF) with crimes less likely to occur the further away an offender is from their home base. It is concerned with the ‘distance of crime’ and that offenders will in general travel limited distances to commit their crimes. Routine Activity Theory Originally developed by Cohen and Felson (1979), the primary principle is that the offender and victim must intersect in time and space for a crime to occur. This approach focuses on the concept that crime occurs when an opportunity is taken within both parties’ non-criminal spatial activity. An activity space may consist of the regular areas an offender travels such as work, school, home or recreational areas. Rational Choice Theory Concepts relating to the explanation of spatial behaviour include the least-effort principle where offenders are more likely to act on the first or opportunity and the idea of a buffer zone. It exhibits a constant tension between the offender’s desire to divert attention from his home base and the desire to travel no further than necessary to commit crimes. Crime Pattern Theory Developed by Canadian environmental criminologists Paul and Patricia Brantingham, the theory exerts the strongest influence in geographic profiling. It suggests that crime sites and opportunities are not random. There is an emphasis in the interaction between the offender’s mental map of spatial surroundings and the allotment of victims (target backcloth). Furthermore, serial crimes are the easiest to develop geographic profiles, since each crime contains new spatial information and provides additional data including the fact that crime area tends to enlarge with an increase of comfort and confidence. The initial hunt and criminal acts are most likely to occur relatively close to the location of the offender's home or workplace. As the success rate increases, there will be a burgeoning sense of confidence to seek his prey further from home and to travel a greater distance. Crimes that are suitable for analysis are those that are predatory in nature and exercises some spatial decision-making process such as the area for hunting targets, travel routes, mode of transportation and even body dump sites. Another leading researcher in this area is David Canter whose approach to geographic profiling detailed around the circle theory of environmental