NxStage Medical, Inc., a medical device company, develops, manufactures, and markets products for the treatment of kidney failure, fluid overload, and related blood treatments and procedures. Its primary product includes the System One, a portable hemodialysis system used for the treatment of acute and chronic kidney failure, and fluid overload. The company operates in three segments: System One, In-Center, and Services. The System One segment engages in the sale and rental of the NxStage System One and PureFlow SL dialysate preparation equipment, and sale of disposable products in the home and critical care markets. The home market focuses on the treatment of end-stage renal disease (ESRD) patients in the home or a home-like setting, and critical care market on the treatment of hospital-based patients with acute kidney failure or fluid overload. The In-Center segment sells blood tubing sets and needles for hemodialysis primarily for the treatment of ESRD patients at dialysis centers; and needles for apheresis. The Services segment provides dialysis services to patients at NxStage Kidney Care dialysis centers. NxStage Medical, Inc. markets its products through direct sales and distributors to hospitals and dialysis centers in the United States and internationally. The company, formerly known as QB Medical, Inc., was founded in 1998 and is headquartered in Lawrence, Massachusetts.