A low cost ultrahigh throughput flow cytometer is proposed. The instrument utilizes a disposable cartridge that essentially eliminates the high maintenance, training, and operating costs associated with flow cytometry. Novel fluidics increase potential throughput to several orders of magnitude faster than conventional flow cytometers, while decreasing manufacturing costs by orders of magnitude. Flow cytometers provide the underpinnings for diagnostics in many fields ? hematology, genetics screening, tissue engineering, drug screening, genomic and proteonomic research, cancer, AIDs, etc. The vast majority of the diagnostics tests using flow cytometry are not routinely available to the general public because of their cost and complexity. This technology takes the cost, skill, and complexity out of flow cytometry, and for the first time allows point-of-care testing. Underserved communities, rural locations, and third world countries could have direct access to many more diagnostic tests. Clinical and basic research will benefit from inexpensive and continuous access to a powerful analytical tool. This ultrahigh throughput flow cytometer is ideally suited to the low gravity environment due to its small size, low power consumption, and gravity independence. POTENTIAL COMMERCIAL APPLICATIONS Ultrahigh throughput flow cytometry address a segment of the $29 billion in vitro diagnostic market. The approach will reduce health care costs and enable point-of-care testing. The combination of cost reduction and point-of-care testing should improve overall health care, as well as health care in previously underserved communities, rural areas, and third world countries. There is strong market pull in the $300 - $800 million niches for genomic/proteonomic/DNA low cost ultrahigh through screening. We believe that substantially lowering screening costs will be a large multiplier for discoveries.