A number of microscopic valve structures have been developed that are based on silicon and use an energy source that is directly connected to the device.1, 2 These are appropriate for many uses, but not for biomedical applications. On the other hand, some researchers have addressed the possibility of using biomedical implants for biotelemetry applications.3 If these devices are to be implanted in an animal or a human body, we need to find a way to make them both biocompatible and remotely actuated. Size, weight, complexity, and security must all be addressed. The shorter the microwave signal frequency, the shorter the penetration depth through water-containing tissues. Therefore, we’d like to find the optimal tradeoff between the interrogation signal frequency and microvalve size.4, 5 Microvalve applications usually require small size and low weight, which creates an upper limit on the antenna size. Also, we would like to have a microvalve that doesn’t incorporate a battery, both because this would decrease the size and weight of the valve and because it would eliminate batteryreplacement requirements. An additional disadvantage of powering the devices by a battery or a capacitor—charged using inductive coupling—for short-term burst operation4, 5 is that these schemes require activemicroelectronics to be integrated with the microvalve. In contrast, we propose using a piezoelectric polymer material with no active microelectronic components.6, 7 This allows the integration of the antenna, interdigital transducer (IDT), surface acoustic wave (SAW) device, and actuator to control the microvalve without batteries on a biocompatible substrate (see Figure 1). We have developed four microvalve structures. Two of them use a bimorph actuation mechanism (see Figure 2), while the Figure 1. An implanted microvalve uses interdigital transducers (IDTs) and a microannetenna to establish a secure wireless connection to exterior devices. Power from the RF pulses is transferred from the surface-acoustic-wave (SAW) device to the micro-actuator to open and close the microvalve.