Silicon became well known as the base material for high performance microstructures on the basis of cost, performance, durability, and excellent mechanical as well as electrical properties. Numerous market surveys and projections have identified a myriad of high volume opportunities over the past two decades. Yet true commercial success has remained in isolated pockets. The appeal of mechanical and electrical on the same miniature device combined with the photogenic resulting structures has resulted in a general hype of the technology. In concept, microstructures in silicon can fill just about any role as a small scale physical to electrical interface. However, the danger lies in assuming that these applications justify the cost. These costs of ownership include infrastructure cost, cost of compensating for performance limits, time to market, and hidden manufacturing costs. Many technically elegant microstructure solutions become solutions looking for problems. This presentation looks first at the opportunity and characteristics of silicon microstructures that make it an enabling technology, followed by examples where the technology has found markets. A summary of the industry characteristics and a comparison and contrast with the traditional electronics industry follows. A profile of successful microstructure applications and future trends leads to insight on how to structure a commercially viable approach. Finally, a summary of the market drivers and requirements and the true cost of ownership provides guidance on markets where a microstructure solution makes sense.