Prior to the full maturation of electro-absorption modulated laser technology, directly modulated 1.55 micrometer distributed feedback lasers will continue to play a central role in long haul, high bit rate, optical communications systems. Maintaining a competitive advantage, however, requires that these devices be optimized for long fiber length transmission, high power, and low cost. In this talk we discuss the design elements needed to accomplish this. Focus is placed on factors leading to reduction of the linewidth enhancement factor, (alpha) . In particular, the role played by complex gratings is examined. We demonstrate typical cw (alpha) values of 1.65 can be achieved in a robust and manufacturable device. This device is shown to readily serve 2.5 Gb/s applications with span lengths of 200 km (approximately 3600 ps/nm).