Within GNS theory, this is a general term for play where everyone shares a focused priority on a single GNS mode or functional hybrid. Game designs are said to be coherent if they clearly encourage play of this sort: in particular by having mechanics which support the GNS mode encouraged by the text. The opposite is Incoherence.

As with Incoherence, although the word "coherence" has a positive connotation, it is still debatable whether what this definition defines is good, bad, some combination, good sometimes and bad sometimes, or simply value-neutral.

References:

• GNS and Other Matters of Role-playing Theory
• Simulationism: The Right to Dream