  The different regimes of gravitational lensing constitutes an interesting
tool in order to map the mass distribution in galaxy clusters on different
scales. In this proceedings article, I review some work I have performed on
this topic. More precisely, I will focus on : (i) galaxy scale substructures,
using weak galaxy-galaxy lensing in order to study how does the environment
shape their properties; (ii) the mass profile of Abell~1689 as probed combining
strong and weak lensing; (iii) the slope of the inner dark matter distribution
in Abell~1703 as measured by strong lensing. The lensing results will be
compared to the expectations from numerical simulations, when available.
