This small package allows a LaTeX document containing the citation commands provided by the Harvard package to be compiled using the natbib package. Migration from harvard to natbib thus can be achieved simply by replacing

\usepackage{harvard}

with

\usepackage{natbib}
\usepackage{har2nat}

It is important that har2nat be loaded after natbib, since it modifies natbib commands.

The author is Bas Straathof.