Matthew Heusser at CIO.com – How to Advance Lean Software Development (Beyond the 'Toyota Way'):

“Lean manufacturing focuses on delivering one part, end-to-end. This is sometimes called one-piece flow. […] To get to one-piece flow, we'll eliminate multi-tasking.

[…] Instead of "pushing" work to the next step in the chain, we pull it. This means testers don't take on work until they are ready for it. […] [The programmers] have to figure out how to help the testers— by testing themselves, perhaps, or by writing test tools or "drivers."

[…] The lean software solution is to get the person who can answer the question in the room—either by embedding the customer directly in the team room, or, for a technical question, pairing new programmers with more experienced staff so they dont get stuck.

[…] When I started at one recent client, the team was doing "book" Scrum, with two-week iterations and bi-weekly ritual meetings that included retrospective, planning and estimating meetings. These meetings often felt forced and artificial. […] We dropped iterations and moved the meetings to a just-in-time format. […] Since we made that switch, two other teams switched to this continuous flow approach; three other teams continue to use iterations. There was no mandate from management or standard to follow. Certain teams simply saw waste and wanted to eliminate it.”