  Primordial black holes (PBHs) are an attractive dark matter candidate,
particularly if they can explain the totality of it. At PBH masses below $\sim
10^{17}$g and above $\sim 10^{23}$g this possibility is excluded from the
variety of arguments and with different confidence. The range in between, often
referred to as the "asteroid mass window", currently remains unconstrained. The
most promising, in our view, way to probe this mass range is to use stars as
the PBH detectors. If a star captures even a single PBH it starts being
accreted onto it and eventually gets destroyed -- converted into a sub-solar
mass black hole. This process may have a variety of signatures form a mere star
disappearance to supernova-type explosions of a new kind. The viability of this
approach depends crucially on the probability of PBH capture by stars. In this
chapter we summarize the existing capture mechanisms and discuss their
implications for constraining the abundance of (or perhaps discovering) PBHs in
the asteroid mass window.
