Background
Reporting organisations can use whichever sector codes they want
They should also be encouraged to publish data using their own internal sector codes as they are likely to be more precise and accurate than the DAC sector codes (e.g. WB Themes and WB Sectors; DFID sector codes)

Problems
Using different codelists presents significant challenges (or barriers) to re-use of the data, especially if the entire codelist is not public.
Donors are encouraged to use the “RO” vocabulary code if they are using their own codelist. Does this make it harder for this to be used (as opposed to putting something more unique to that codelist in the vocabulary code)?
It would also make the budget identifier much more straightforward if both reporting organisations and info-/intermediaries could take a reporting organisation’s sector codes and map them across to recipient country budget classifications.

Proposal
All reporting organisations should publish a comprehensive list of their sector codes (text and code), if they are using their own internal code lists.
Perhaps:
reporting organisations should map this list of sector codes to the DAC, or another common set of sector codes?

Proposed by Mark Brough