The Supreme Court's judgment proves that in Polish contractual practice appear some new standard contractual clauses. Those clauses are mostly issued by banks and insurers (pursuant to Article 384 of the Civil Code) in order to protect the debtor (e.g. constructions work contractor) in case the creditor (investor) unjustifiaby uses the so-called a guarantee “on first demand”. One of such clauses is a clause that provides for creditor’s contractual liability towards the debtor (as part of the so-called basic relationship, e.g. construction contracts). The author analyzes the nature and purpose of such clauses. The judgemet of the Supreme Court inspires the author to indicate other clauses that result from the loyal cooperation of the guara...