Scaling Up vs Scaling Out

(1) Concerned with using agile methods for large software systems that cannot be developed by a small team,Scaling up

(2) Concerned with how agile methods can be introduced across a large organisation with many years of software development experience,Scaling out

(3) Requires more up-front design, cross-team communication mechanisms, and frequent system builds,Scaling up

(4) Requires cultural change, management evangelism, and addressing quality standard incompatibilities,Scaling out

Explanation

Scaling up: using agile for large systems — requires more up-front design, cross-team communication mechanisms, and frequent system builds. Scaling out: introducing agile across a large organisation — requires cultural change, management buy-in, and addressing conflicts with existing quality standards and procedures.