Unintegrated parton density functions

An overview on activities to determine unintegrated parton density functions is given and the concept and need for unintegrated PDFs is discussed. It is also argued that it is important to reformulate perturbative QCD results in terms of fully unintegrated parton densities, differential in all components of the parton momentum. Also the need for non-linear BFKL evolution is discussed and results using the BK equation supplemented by DGLAP corrections at short distances is reviewed. Finally the use unintegrated generalized parton distributions for hard diffractive processes is discussed