  Model sets are always Meyer sets, but not vice-versa. This article is about
characterizing model sets (general and regular) amongst the Meyer sets in terms
of two associated dynamical systems. These two dynamical systems describe two
very different topologies on point sets, one local and one global. In model
sets these two are strongly interconnected and this connection is essentially
definitive. The paper is set in the context of multi-colour sets, that is to
say, point sets in which points come in a finite number of colours, that are
loosely coupled together by finite local complexity.
