Techniques for adaptively tuning an impedance matching circuit are disclosed. In an aspect, the impedance matching circuit is pre-characterized. The performance of the impedance matching circuit is determined for multiple settings of the impedance matching circuit, stored in memory, and used to tune the impedance matching circuit. In another aspect, the impedance matching circuit is tuned based on measurements for one or more parameters such as delivered power, return loss, power amplifier current, antenna/load impedance, etc. In an exemplary design, an apparatus includes a memory and a control unit. The memory stores information for multiple settings of an impedance matching circuit. The control unit selects one of the multiple settings of the impedance matching circuit based on the information for the multiple settings and measurements for the impedance matching circuit. The impedance matching circuit performs impedance matching for a load circuit (e.g., an antenna) based on the selected setting.