Upper gut transit and motility among 10 symptomatic and 9 asymptomatic patients with Roux gastrectomy were compared with those among 10 healthy, unoperated controls. Gastric emptying of solids and Roux limb and small intestinal transit of liquids were assessed scintigraphically. Motor patterns in the Roux limb or healthy jejunum were recorded manometrically. Whereas gastric emptying was sometimes faster and sometimes unchanged after Roux gastrectomy compared with controls, Roux limb transit in patients was consistently slower than jejunal transit in controls. Postprandially, the Roux limb showed decreased overall motility, fewer clustered waves, and less aboral migration of clustered waves than the healthy jejunum. Symptomatic Roux patients had jejunal transit and motor patterns similar to those of asymptomatic patients. Nonetheless, reflux from Roux limb to gastric remnant occurred in 4 of 10 symptomatic patients but in none of the asymptomatic patients. In conclusion, stasis and dysmotility are present in the Roux limb after Roux gastrectomy and Roux-gastric reflux can occur. Other factors, however, must have a role in determining whether symptoms appear.