We prove the Strominger-Yau-Zaslow mirror symmetry conjecture for non-compact Calabi-Yau surfaces arising from, on the one hand, pairs ( Y , Ď) of a del Pezzo surface Y and Ď a smooth anticanonical divisor and, on the other hand, pairs (Y, D) of a rational elliptic surface Y , and D a singular fiber of Kodaira type I k . Three main results are established concerning the latter pairs (Y, D). First, adapting work of Hein [25], we prove the existence of a complete Calabi-Yau metric on Y \D asymptotic to a (generically non-standard) semi-flat metric in every Kähler class. Secondly, we prove an optimal uniqueness theorem to the effect that, modulo automorphisms, every Kähler class on Y \ D admits a unique asymptotically semi-flat Calabi-Yau metric. This result yields a finite dimensional Kähler moduli space of Calabi-Yau metrics on Y \ D. Further, this result answers a question of Tian-Yau [40] and settles a folklore conjecture of Yau [43] in this setting. Thirdly, building on the authors' previous work [9], we prove that Y \D equipped with an asymptotically semi-flat Calabi-Yau metric ωCY admits a special Lagrangian fibration whenever the de Rham cohomology class of ωCY is not topologically obstructed. Combining these results we define a mirror map from the moduli space of del Pezzo pairs ( Y , Ď) to the complexified Kähler moduli of (Y, D) and prove that the special Lagrangian fibration on (Y, D) is T -dual to the special Lagrangian fibration on ( Y , Ď) previously constructed by the authors in [9]. We give some applications of these results, including to the study of automorphisms of del Pezzo surfaces fixing an anti-canonical divisor.