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diff --git a/doc/documentation.tex b/doc/documentation.tex
index ac5251f..73982d0 100644
--- a/doc/documentation.tex
+++ b/doc/documentation.tex
@@ -65,6 +65,8 @@ PUGH can be compiled with or without MPI. Compiling without MPI results
 in an executable which can only be used on a single processor, compiling 
 with MPI leads to an executable which can be used with either single or
 multiple processors.
+(Section~\ref{pugh_understanding} describes how you can tell if your
+executable has been compiled with or without MPI).
 
 For configuring with MPI, see the Cactus User's Guide.
 
@@ -177,6 +179,66 @@ pugh::partition_2d_y=''15:15''
 
 
 Note that an empty string for a direction will apply the automatic distribution.
+\section{Understanding PUGH Output}
+
+\label{pugh_understanding}
+
+PUGH reports information about the processor decomposition to standard output 
+at the start of a job. This section described how to interpret that output.
+
+\vskip .3cm
+
+\noindent
+{\bf Single Processor (no MPI)}
+
+\begin{itemize}
+
+\item{\bf Type of evolution}
+
+If an executable has been compiled for only single processor use
+(without MPI), the first thing which PUGH reports is this fact:
+
+{\tt INFO (PUGH): Single processor evolution}
+
+\end{itemize}
+
+
+\vskip .3cm
+
+\noindent
+{\bf Multiple Processor (with MPI)}
+
+
+
+\vskip .3cm
+
+\begin{itemize}
+
+\item{\bf Type of evolution}
+
+If an executable has been compiled using MPI, the first thing which 
+PUGH reports is this fact, together with the number of processors
+being used:
+
+{\tt INFO (PUGH): MPI Evolution on 3 processors}
+
+
+\item{\bf Maximum load skew} 
+
+The maximum load skew describes the variance in the number of gridpoints on
+each processor, and is defined by
+
+$$\mbox{Max Skew} = 100 \;\;\frac{\mbox{Max Points}- \mbox{Min Points}}{\mbox{Average Points}} $$
+
+For most purposes, the maximum skew should ideally be close to zero,
+however if your simulation has a different load at different grid
+points, or if you are running across processors with different
+properties, the optimal skew could be quite different.
+
+By default, PUGH tries to minize the skew in gridpoints, however this may
+be overriden by performing the load balancing manually.
+
+\end{itemize}
 
 \section{Useful Parameters}