Most of the ideas in &SCons; originate with &Cons;, a Perl-based software construction utility that has been in use by a small but growing community since its development by Bob Sidebotham at FORE Systems in 1996. The &Cons; copyright was transferred in 2000 from Marconi (who purchased FORE Systems) to the Free Software Foundation. I've been a principal implementer and maintainer of &Cons; for several years. &Cons; was originally designed to handle complicated software build problems (multiple directories, variant builds) while keeping the input files simple and maintainable. The general philosophy is that the build tool should ``do the right thing'' with minimal input from an unsophisticated user, while still providing a rich set of underlying functionality for more complicated software construction tasks needed by experts. In 2000, the Software Carpentry sought entries in a contest for a new, Python-based build tool that would provide an improvement over Make for physical scientists and other non-programmers struggling to use their computers more effectively. Prior to that, the idea of combining the superior build architecture of &Cons; with the easier syntax of Python had come up several times on the cons-discuss mailing list. The Software Carpentry contest provided the right motivation to spend some actual time working on a design document. After two rounds of competition, the submitted design, named ScCons, won the competition. Software Carpentry, however, did not immediately fund implementation of the build tool, instead contracting for additional, more detailed draft(s) of the design document. This proved to be not as strong motivation as actual coding, and after several months of inactivity, I essentially resigned from the Software Carpentry effort in early 2001 to start working on the tool independently. After half a year of prototyping some of the important infrastructure, I accumulated enough code to take the project public at SourceForge, renaming it &SCons; to distinguish it slightly from the version of the design that won the Software Carpentry contest while still honoring its roots there and in the original &Cons; utility. And also because it would be a teensy bit easier to type.