We investigate whether long audit partner tenures impair auditor independence, as proxied by the opinion of the audit report, with a sample of Spanish companies for the period: 2002-2010. The Spanish audit market constitutes an ideal setting in which to address this issue, as it is characterized by unusually lengthy engagements with the audit firm. The motivation relies, on the one hand, on the current discussion about the necessity to reinforce the independence of auditors and, on the other hand, on the very limited available research at the partner level. The main result is the lack of significant effects of partner tenure on independence. This finding is robust to various checks. Unlike prior research, we also address the joint effects of firm and partner tenure on independence. Results indicate that partner tenure does not compromise independence, even under long or extremely long audit firm tenures. These findings might have some interesting policy implications, in particular for the intense current debate on auditor rotation regimes which is taking place within the European Union.