diff --git a/README.md b/README.md
index 5250ac5..51c1b53 100644
--- a/README.md
+++ b/README.md
@@ -10,3 +10,45 @@ It is based loosely around a combination of both Arch's
 makepkg system and FreeBSD's ports tree.
 
 It is very much a work in progress and liable to break any time.
+
+
+How it works
+------------
+
+Package compilation is based around a reasonably simple POSIX `sh`
+script (NOT a `bash` script, so many things you may be used to just
+aren't there!). The script contains two main sections.
+
+1. Declarations and Definitions
+
+These are a list of shell variables that describe the package:
+
+  * VERSION - The version number of the package
+  * PACKAGE - The name of the package (must be the same as the
+    package directory name)
+  * CATEGORY - The category the package is in (must be the same
+    as the directory the package directory resides in)
+  * SRC - The source filename once downloaded - not needed for GIT downloads
+  * URL - The URL to get the source from (see below)
+  * DEPENDS - A list of packages that should be compiled and installed
+    before this one.
+
+2. Operational Functions
+
+These do the actual work of compiling the sofware. Three are essential:
+
+  * configure() - Configure the source (usually running ./configure etc)
+  * build() - Compile the source
+  * install() - Install it to `${DESTDIR}`
+
+Compiling a Package
+-------------------
+
+Simply run `makepkg` in a package folder and it should compile into
+a standard Solaris package file for you.  There are some command line
+options:
+
+* -i : Install the package after compiling it.
+* -s : Compile and install any dependencies of this package first
+       before compiling this package
+* -f : Force a clean rebuild of the package from scratch