In an economic context marked by inflation, market volatility, and rising financing and production costs, the performance of long-term contracts can become significantly more demanding than what the parties anticipated at the time of entering into them.

The question that arises is not merely economic. Above all, it is legal: to what extent can, or should, a contract adapt to a substantial change in the circumstances that formed the basis of the decision to contract?

The principle pacta sunt servanda remains the starting point. Under Article 406 of the Portuguese Civil Code, contracts must be strictly complied with, reflecting the binding force of the agreement and the need to ensure trust and predictability in legal relations.

However, the binding force of a contract does not necessarily mean its absolute immutability. Article 437 of the Portuguese Civil Code provides, in exceptional circumstances, for the possibility of modifying or terminating the contract when an abnormal change of circumstances, forming the basis of the transaction, causes a severe impact on the position of one of the parties, in terms incompatible with good faith.

The application of this regime requires a particularly rigorous analysis. Price or cost increases do not, in themselves, constitute sufficient grounds to alter a contract. It will be necessary to evaluate, among other factors, the predictability of the change, the nature and duration of the contract, the contractual allocation of risks, the existence of price indexation or revision clauses, and the actual dimension of the economic impact on the contractual relationship.

It is precisely in this domain that legal advice assumes a strategic dimension.

A lawyer’s intervention should not arise only when an economic imbalance has already escalated into default or litigation. Preventative contract analysis allows for early identification of risks, assessment of the sufficiency of existing revision mechanisms, and structuring of solutions that offer greater responsiveness to relevant changes in the economic context.

Renegotiation can thus take various forms: price revision, introduction of indexation mechanisms, alteration of payment terms or deadlines, adjustment of obligations, or inclusion of hardship clauses. When properly structured, these solutions can preserve the contractual relationship by distributing the effects of an adverse economic climate more equitably.

Rather than seeking uniform responses to complex economic phenomena, the key is understanding where the normal risk of a contract ends and where a legally relevant change in its premises begins.

In an uncertain economic environment, legal certainty does not stem solely from the stability of the contract. It also stems from the ability to anticipate risks, correctly interpret available legal mechanisms, and negotiate legally sustainable solutions.

It is through this forward-thinking approach that business-focused legal advisory adds true value: not only in resolving conflicts, but in preventing them and, above all, in drafting contracts built to withstand change.