TRADE AGREEMENTS
Formalized economic relationships between factions — trade routes established by treaty, per-turn resource exchanges, open-market access granted and revoked, embargoes as economic warfare.
- SOLO-DEV COST MEDIUM
- TIMING REAL-TIME / TURN
- COMMON IN 4X · GRAND-STRATEGY · STRATEGY · MMO
Civilization's trade deals are the reference structure (luxury swaps, gold-per-turn arrangements, open borders as tradeable commodity — the deal screen is a marketplace of everything), Europa Universalis embeds trade in nodes and merchant steering where agreements shape flows, Stellaris signs commercial pacts and federations with economic clauses, and MMO player-alliances negotiate resource treaties no interface supports (EVE's coalition logistics are trade agreements written in spreadsheets and trust). Designers formalize trade because recurring exchange builds relationships that one-off deals can't: a per-turn agreement is a standing mutual interest — both parties now profit from each other's survival, so the trade network becomes a peace infrastructure (war with your best customer is expensive by construction), and diplomacy acquires an economic gradient between friendship and hostility, letting relations warm or cool through commerce before anyone commits to alliance or war. Agreements also make interdependence a strategic choice with teeth: specializing your economy and trading for the rest is efficient and vulnerable (the embargo is a siege without soldiers — cutting a dependent partner's imports is warfare with plausible deniability), and reading the map's trade web reveals the real alliance structure underneath the stated one. The termination clause is where the mechanic lives: deals that end (expiry, cancellation, violation) create renewal negotiations, leverage moments, and the distinctive betrayal of the canceled agreement timed to a war declaration. Key decisions: deal vocabulary breadth (resources, gold, access, promises — the richer the tradeable set, the more diplomacy becomes economics), duration and cancellation rules (locked terms versus at-will exit — friction here determines whether agreements are commitments or suggestions), AI valuation transparency (players must roughly understand why the AI accepts or refuses, or negotiation is slot-machine diplomacy), and third-party visibility — public deals let the map react; secret ones enable the double-cross. Pitfall: agreements as free value taps — when the AI accepts trades that are pure player profit (the classic luxury-for-everything exploit), the diplomatic economy becomes a farming mechanic and every deal screen a harvest; trade agreements only model relationships when both sides' benefit is real, because a partner who profits nothing is not a partner, just an ATM with a flag.