Function Mapping (OD)

Theory & origin

The method descends from Porter’s value-chain analysis (1985) and the activity analysis tradition in organization design — Galbraith’s premise that structure should follow the work, not the other way around. In practice OD teams inventory functions top-down (value chain → functions → activities) and bottom-up (what people actually spend time on), then attach FTE and cost to each activity. The map exposes what org charts hide: the same activity performed in four units, critical work owned by nobody, and shadow functions that grew inside departments because the official one was too slow. Restructuring without this layer is rearranging labels on unknown contents.

How a consultant runs it

1. 01 Anchor on the value chain first: what must this organization be able to do, end to end, regardless of who does it today.
2. 02 Inventory activities both top-down and bottom-up — the gap between the official decomposition and the time-study reality is itself a finding.
3. 03 Attach FTE and cost to every activity; a map without numbers is a poster, not a case.
4. 04 Hunt the three patterns: duplication (same activity, many homes), fragmentation (one activity, split thin across units), and orphans (critical work, no owner).
5. 05 Only then design: consolidate, centralize or federate per activity with the numbers attached — and hand the map to job family mapping as its input.

Worked example

A 1,200-FTE services firm wants 15% cost out of corporate functions and proposes proportional cuts. The function map tells a different story: management reporting is performed in four separate units totalling 22 FTE with three different toolchains, procurement is fragmented across every business unit at 0.5 FTE each — below critical mass everywhere — and contract management is an orphan nobody owns since the last reorg. The redesign consolidates reporting into one team of 14, pools procurement into a centre of 9, and gives contracts a home. The saving beats the target without the across-the-board cut that would have damaged the functions that were already lean.

Common pitfalls

1. 01 Mapping departments instead of work, faithfully reproducing the org chart the exercise exists to see past
2. 02 Skipping FTE and cost attribution, leaving a diagram with no case attached
3. 03 Letting unit heads self-report activities without triangulation — everyone owns everything, nobody duplicates anything
4. 04 Stopping at the map: findings without redesign decisions and owners change nothing

Sample deliverable

One real engagement, end to end — watch the numbers travel from raw input, onto the chart, into the artifact.