Understanding the complex crystallization behavior of isotactic polypropylene (iPP) in conditions comparable to the one found in injection moulding, where the polymer melt experiences a combination of high shear rates and elevated pressures, is key for modeling and, therefore, predicting the final structure and properties of iPP products. Coupling a unique experimental setup, capable to apply wall shear rates similar to the ones experienced during processing and carefully control the pressure before and after flow is imposed, with in-situ X-ray scattering and diffraction techniques (SAXS and WAXD) at fast acquisition rates (up to 30 Hz), a well-defined series of short-term flow experiments are carried on using 16 different combinations of wall shear rates (ranging from 110 to 440 s−1) and pressures (100-400 bar). A complete overview on the kinetics of structure development during and after flow is presented. Information about shish formation and growth of α-phase parents lamellae from the shish backbones is extracted from SAXS; the overall apparent crystallinity evolution, amounts of different phases (α, β and γ), and morphologies developing in the shear layer (parents and daughters lamellae both in α and γ phase) are fully quantified from the analysis of WAXD data. Both, flow rate and pressure were found to have a significant influence on both the nucleation and the growth process of oriented and isotropic structures. Flow affects both shish formation and the growth of α-parents, pressure acts both on relaxation times, enhancing the effect of flow, and (mainly) on the growth rate of γ-phase. The remarkably high amount of γ-lamellae found in the oriented layer strongly suggested the nucleation of γ directly from the shish backbone. All the observations were conceptually in agreement with the flow induced crystallization model framework developed in our group, and represents a unique and valuable dataset that will be used to further validate and implement our numeric