Canonical problems are simplified representations of a class of real world problems. They allow researchers to compare algorithms in a standard setting which captures the most important challenges of the real world problems being modeled. Such examples are the block world for planning, two-player games for algorithms which learn the behavior of the opponent agent, or the "split the pie" game for a large class of negotiation problems.

In this paper we focus on negotiating collaboration in space and time, a problem with many important real world applications. Although technically a multi-issue negotiation, we show that the problem can not be represented in a satisfactory manner by the split the pie model. We propose the "children in the rectangular forest" (CRF) model as a possible canonical problem for negotiating spatio-temporal collaboration. By exploring a centralized and a peer-to-peer negotiation based solution, we demonstrate that the problem captures the main challenges of the real world problems while allows us to simplify away some of the computationally demanding but semantically marginal features of real world problems.