  Several philosophical issues in connection with computer simulations rely on
the assumption that results of simulations are trustworthy. Examples of these
include the debate on the experimental role of computer simulations
\cite{Parker2009, Morrison2009}, the nature of computer data
\cite{Barberousse2013, Humphreys2013}, and the explanatory power of computer
simulations \cite{Krohs2008, Duran2017}. The aim of this article is to show
that these authors are right in assuming that the results of computer
simulations are to be trusted when computer simulations are reliable processes.
After a short reconstruction of the problem of \textit{epistemic opacity}, the
article elaborates extensively on \textit{computational reliabilism}, a
specified form of process reliabilism with computer simulations located at the
center. The article ends with a discussion of four sources for computational
reliabilism, namely, verification and validation, robustness analysis for
computer simulations, a history of (un)successful implementations, and the role
of expert knowledge in simulations.
