Differential cross sections for 201.5 MeV proton scattering from 88Sr were measured. From the analysis of the elastic data, no unique optical-model potential could be obtained, but the radial moments are well determined. In a macroscopic analysis of the collective states it turns out that if the optical potential and transition potential are chosen consistently, unambiguous potential deformation lengths can be obtained even though the optical potential is not unique. Taking into account the range and density dependence of the underlying effective interaction reliable neutron deformation lengths can be obtained. For inelastic transitions of various character microscopic distorted-wave calculations with a density-dependent interaction based on the Paris potential were performed. The nuclear structure was taken from one broken-pair calculations in a large model space, calibrated by (e,e′) data. In general a good description is obtained for states with spins ranging from 2 + to 10 −. These calculations indicate that the central spin-independent part of the effective interaction is slightly too strong, while the spin-orbit part seems to be too weak or too weakly density dependent.