The condition in which two or more organizational units, agencies, or roles perform substantially similar tasks or responsibilities within an operational domain, producing redundancy of capability and potential ambiguity about authority, accountability and coordination.

Principle

Overlap creates both redundancy (which can increase resilience) and role ambiguity or coordination costs (which can reduce efficiency and accountability); the net effect depends on governance mechanisms, clarity of mandates, and the frequency and stakes of required coordination.

Demonstration

Illustrative scenario → Two municipal departments and a regional agency each maintain emergency shelter activation authority for the same jurisdiction; without an agreed protocol, shelters may be duplicated, resources misallocated, or citizens receive mixed guidance, while a prearranged division of duties or joint command can harness redundancy for resilience.

Misapplication

Labeling any instance of shared responsibility as harmful duplication; the error is ignoring whether overlap is intentional contingency planning or accidental unclear mandate, and whether coordination mechanisms mitigate costs.

Consequence

Affects resource allocation, crisis response, and public accountability: unmanaged overlap increases transaction costs, slows decision-making, and obscures liability; well-managed overlap can provide backup capacity and cross-checks but may impose fiscal and coordination overheads.

Reversal

When tasks are high-risk and require fail-safe capabilities, intentional overlap (designed redundancy) is desirable; conversely, in low-ambiguity routine tasks, overlap more often produces inefficiency and should be streamlined.

Boundary

Within: substantial similarity of tasks leading to potential confusion about who acts and who is accountable. Boundary case: formal joint ventures or shared-service centers where tasks are duplicated by design but governed by clear rules. Outside: mere collaboration or referral relationships where tasks remain distinct and authority is unambiguous.

Semantic Tension

Redundancy/Resilience ↔ Efficiency/Accountability — overlap trades off backup capacity against clarity and cost, forcing governance choices about when to centralise, delegate, or duplicate functions.

Synthesis

Functional overlap is a governance design problem: it is neither intrinsically good nor bad but must be managed by rules, protocols and authority assignments so that redundancy yields resilience without unduly sacrificing efficiency and clear accountability.