The domain configuration and the electromechanical related properties have been studied in Pb[(Zn1/3Nb2/3)0.91Ti0.09]O3 (PZN-9%PT) single crystals cut along [001] and [101̄]. It was established that soft (with high d) and hard (with lower d) piezoelectric properties are respectively obtained in a multidomain and a single domain configuration. The softer piezoelectric material (d33 - 2700 pC/N, S33 E = 180 pN/m2, k33 = 93%) was found in the monoclinic multidomain state after poling with a small field along [001]. Optimal poling process and electromechanical related properties of the single crystals were discussed in term of the field-temperature diagram.