Various models describing the stationary temperature-induced phenomenon of spin crossover in metal complexes are briefly discussed. The emphasis is put on the usability of the presented models as tools for the quantitative interpretation of experimental data. The empirical approaches are first reviewed, which are usually called thermodynamic models or Ising-like models depending on their macroscopic or microscopic representation. These form a suitable reference base for the other, more principal approaches that covers ligand field models, elasticity models and vibronic models for which interpretation of the ad hoc parameters is offered and eventually new consequences are appearing. Finally, insight into Monte Carlo modelling is presented, which appears as a perspective for theoretical analysis of spin transition.