MoSCoW method

The MoSCoW method is a prioritization technique used in management, business analysis, project management, and software development to reach a common understanding with stakeholders on the importance they place on the delivery of each requirement - also known as MoSCoW prioritization or MoSCoW analysis.

The term MoSCoW itself is an acronym derived from the first letter of each of four prioritization categories (Must have, Should have, Could have, and Won't have but would like), with the interstitial Os added to make the word pronounceable. While the Os are usually in lower-case to indicate that they do not stand for anything, the all-capitals MOSCOW is also used.

This prioritization method was developed by Dai Clegg and first used extensively with the agile project delivery framework Dynamic Systems Development Method (DSDM).

MoSCoW is often used with timeboxing, where a deadline is fixed so that the focus must be on the most important requirements, and as such is a technique commonly used in agile software development approaches such as Scrum, rapid application development (RAD) and DSDM.

All requirements are important, but they are prioritized to deliver the greatest and most immediate business benefits early. Developers will initially try to deliver all the Must have, Should have and Could have requirements but the Should and Could requirements will be the first to be removed if the delivery timescale looks threatened.

The plain English meaning of the prioritization categories has value in getting customers to better understand the impact of setting a priority, compared to alternatives like High, Medium and Low.

The categories are typically understood as:

In new product development, particularly those following agile software development approaches, there is always more to do than there is time or funding to permit (hence the need for prioritization).

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