An arbitration clause contained in a professional services contract is not enforceable against a party nor does it produce effects precluding judicial proceedings where the contract containing it has been terminated and the obligation has continued de facto between the parties without the formalisation of a new agreement, given that provisions relating to the referral of disputes to arbitration, as well as those concerning mandatory contractual mediation, remain confined to the original contractual relationship and do not automatically extend to relationships continued on a purely de facto basis following termination of the contract.