1 INTRODUCTION
2 WHY WE NEED GALAXY MODELS
3 TYPES OF GALAXY MODEL
3.1 N-body models
3.2 Torus models
4 ASSESSING A MODEL
4.1 Basic notation
4.2 Binning the data
5 OPTIMIZING THE DF
5.1 How many tori do we need?
6 TESTS
6.1 The adopted luminosity function
6.2 The adopted gravitational potential
6.3 The adopted distribution function
6.4 Constructing a pseudo-catalogue
6.5 Case of only a thin disc
6.6 Case of both thin and thick discs
7 DISCUSSION
8 CONCLUSIONS