\documentclass{article}
\usepackage[demo]{graphicx}
\usepackage{subfig}
\begin{document}
\begin{figure}
\begin{tabular}{cccc}
\subfloat[caption]{\includegraphics[width = 1.5in]{something}} &
\subfloat[caption]{\includegraphics[width = 1.5in]{something}} &
\subfloat[caption]{\includegraphics[width = 1.5in]{something}} &
\subfloat[caption]{\includegraphics[width = 1.5in]{something}}\\
\subfloat[caption]{\includegraphics[width = 1.5in]{something}} &
\subfloat[caption]{\includegraphics[width = 1.5in]{something}} &
\subfloat[caption]{\includegraphics[width = 1.5in]{something}} &
\subfloat[caption]{\includegraphics[width = 1.5in]{something}}\\
\subfloat[caption]{\includegraphics[width = 1.5in]{something}} &
\subfloat[caption]{\includegraphics[width = 1.5in]{something}} &
\subfloat[caption]{\includegraphics[width = 1.5in]{something}} &
\subfloat[caption]{\includegraphics[width = 1.5in]{something}}\\
\subfloat[caption]{\includegraphics[width = 1.5in]{something}} &
\subfloat[caption]{\includegraphics[width = 1.5in]{something}} &
\subfloat[caption]{\includegraphics[width = 1.5in]{something}} &
\subfloat[caption]{\includegraphics[width = 1.5in]{something}}
\end{tabular}
\caption{4 x 4}
\end{figure}
\end{document}