Microfabrication and micromachining are terms that describe the technologies and processes used in making microscopic structures or devices. These structures can range in size from the width of a human hair down to smaller than a single human cell. The ability to build devices this small has spurred technological advancements in computers, consumer electronics, green energy technology and many other fields. Microfabrication techniques vary widely depending on the device being built. Infrequent and clinically insignificant fluid retention was observed at the most effective doses. Additional trials using ETA blockers are ongoing or being planned in patients with diabetic nephropathy or focal segmental glomerulosclerosis. Moving forward, such studies must be conducted with careful patient selection and attention to dosing in order to minimize adverse side effects. Nonetheless, there is cause for optimism that this class of agents will ultimately prove to be effective for the treatment of CKD