SDL Inc. proposes to develop novel integrated-modulator 1.55 um laser sources with several important advantages for wavelength division multiplexing systems including a highly repeatable, low cost manufacturing process for laser-modulator monolithic integration and accurate wavelength control in the manufacturing process. In Phase I SDL will demonstrate the basic device design, fabrication, and characterization. In Phase II, the high-speed single-chip modulator will be further optimized, fully DC and RF characterized, and a robust, compact fiber-coupled package will be developed suitable for deployment in various environments. The integrated-modulator laser source will provide the basis for future highly-yielded, low-cost commercial transmitter modules for high-speed long-haul WDM systems.