Modeling at porescale used to be impossible and today it is a reality, thanks largely to the availability of data from imaging, and to high computing power available. Flow, transport, and porescale evolution can be simulated quite accurately in the complex porescale domains, and the "only" remaining question is what to do with the results. In the talk we first describe our past approaches to modeling flow from pore- to core-scale starting with Navier-Stokes equations, and how we use these results from our "virtual laboratory" to derive models valid at the core- or Darcy scale. Next we describe ongoing work on processes with which the porescale geometry changes such as phase transitions modeled with phase-field models, and/or biocementation. The big picture of such porescale modeling, i.e., the "why", will be emphasized, in addition to the "what", and "how".