  In this paper we deal with radiation from heavy quarks in the context of
next-to-leading order calculations matched to parton shower generators. A new
algorithm for radiation from massive quarks is presented that has considerable
advantages over the one previously employed. We implement the algorithm in the
framework of the ${\tt POWHEG-BOX}$, and compare it with the previous one in
the case of the ${\tt hvq}$ generator for bottom production in hadronic
collisions, and in the case of the ${\tt bb4l}$ generator for top production
and decay.
