Subversion is built on a portability layer called APR—the Apache Portable Runtime library. The APR library provides all the interfaces that Subversion needs to function on different operating systems: disk access, network access, memory management, and so on. While Subversion is able to use Apache as one of its network server programs, its dependence on APR does not mean that Apache is a required component. APR is a standalone library usable by any application. It does mean, however, that like Apache, Subversion clients and servers run on any operating system that the Apache httpd server runs on: Windows, Linux, all flavors of BSD, Mac OS X, NetWare, and others.

The easiest way to get Subversion is to download a binary package built for your operating system. Subversion's web site (http://subversion.tigris.org) often has these packages available for download, posted by volunteers. The site usually contains graphical installer packages for users of Microsoft operating systems. If you run a Unix-like operating system, you can use your system's native package distribution system (RPMs, DEBs, the ports tree, etc.) to get Subversion.

Alternatively, you can build Subversion directly from source code, though it's not always an easy task. (If you're not experienced at building open source software packages, you're probably better off downloading a binary distribution instead!) From the Subversion web site, download the latest source code release. After unpacking it, follow the instructions in the INSTALL file to build it. Note that a released source package may not contain everything you need to build a command-line client capable of talking to a remote repository. Starting with Subversion 1.4 and later, the libraries Subversion depends on (apr, apr-util, and neon) are distributed in a separate source package suffixed with -deps. These libraries are now common enough that they may already be installed on your system. If not, you'll need to unpack the dependency package into the same directory where you unpacked the main Subversion source. Regardless, it's possible that you may want to fetch other optional dependencies such as Berkeley DB and possibly Apache httpd. If you want to do a complete build, make sure you have all of the packages documented in the INSTALL file.

If you're one of those folks that likes to use bleeding-edge software, you can also get the Subversion source code from the Subversion repository in which it lives. Obviously, you'll need to already have a Subversion client on hand to do this. But once you do, you can check out a working copy of the Subversion source repository from http://svn.collab.net/repos/svn/trunk/: ^[59]

$ svn checkout http://svn.collab.net/repos/svn/trunk subversion
A    subversion/HACKING
A    subversion/INSTALL
A    subversion/README
A    subversion/autogen.sh
A    subversion/build.conf
…

The preceding command will create a working copy of the latest (unreleased) Subversion source code into a subdirectory named subversion in your current working directory. You can adjust that last argument as you see fit. Regardless of what you call the new working copy directory, though, after this operation completes, you will now have the Subversion source code. Of course, you will still need to fetch a few helper libraries (apr, apr-util, etc.)—see the INSTALL file in the top level of the working copy for details.