How does a shared-service budget fit together?

A community may want its library, park and streets cared for at the same time, but it has only a limited amount to spend. A budget brings those plans together so the group can see what its available resources will cover.

The fictional community has twelve tokens for one period. It allocates four to library service, three to the park and three to street repair. An allocation is an amount set aside for a particular use. These promises total ten tokens, leaving two unallocated and still available.

Giving a service more tokens uses that remainder or requires another change. If all twelve have already been promised, an extra allocation needs fewer tokens elsewhere or more resources. Under this example's no-borrowing rule, the same token cannot cover two separate promises.

A plan that stays within the limit is feasible: its stated uses can be covered. That does not establish which plan people should prefer or whether every need is met. The budget makes the tradeoff visible so people can discuss choices using the same account of what remains.