Clausula rebus sic stantibus

*Clausula rebus sic stantibus* expresses the idea that a contract may be adjusted when extraordinary, unforeseeable changes make performance fundamentally different from what the parties assumed. Swiss law applies the doctrine restrictively, balancing contractual certainty with good faith. It is relevant where strict performance would be intolerable because the contractual equilibrium has collapsed, but not for ordinary market fluctuations or bad bargains. Possible consequences include renegotiation pressure, judicial adaptation, or termination, depending on the circumstances and contract terms.