An assay device for the detection of analyte in a sample, methods and immunoassay formats for performing an assay with or without the device, and methods for manufacturing the device are provided. The device is a continuous liquid flow channel having a proximal and a distal end, with a detection membrane in fluid communication with the distal end of the flow channel. Interspersed between the assay buffer and detection membrane, and continuous with the liquid flow channel, are a sample delivery means, one or more reservoirs containing the reagents necessary for conducting the assay, and, optionally, mixing or incubation reservoirs for combining the sample and reagents. The geometry of the liquid flow channel regulates the flow rate of the liquids through the channel, thereby controlling incubation, mixing and reaction time. The preferred detection membrane is an immunochromatographic test strip containing immobilized reagents. The detection of labeled reagent in a particular area of the detection membrane reflects the presence or relative amount of analyte in the sample. Detection may be achieved visually. One or more liquid flow channels may be contained within a single housing for simultaneous, consecutive, or comparative sample analysis.