Better understanding of factors contributing to live release (rehoming) may help shelters improve outcomes. In this cross-sectional, exploratory, non-interventional study, data for all intakes (n = 21,409) for dogs eligible for rehoming from 1 January 2015 to 31 December 2016 are analyzed to identify such factors. Live release was >88%. A total of 1510 (7.1%) dogs interacted with the foster care system, 98.9% of whom had live release. Foster care increased the odds of live release by about five-fold for all dogs (odds ratio (OR) 5.30 (95% confidence interval (CI): 3.13; 8.97), p < 0.001) and by >20-fold for adult dogs (OR 22.2 (95% CI: 5.48; 90.2), p < 0.001) compared to first-time owner-surrendered dogs. Dogs returned from foster care had a 70% reduction in health concerns, as judged by intake staff, compared with dogs sent to foster. In addition to saving 2882 lives, the rescue network utilized by this shelter was estimated as having reduced in-shelter care needs by 13,409 animal care-days over two years. Dogs returned from adoption also had increased odds of live release (OR 4.74 (95% CI: 3.02; 7.44), p < 0.0001). Nearly a third (29.6%) of dogs originally brought in by owners for euthanasia were determined to be potentially savable, and a fifth of the original group (21.1%) were ultimately placed. Less than 4% of dogs presented with behavioral concerns at intake. It remains to be determined whether other large, open intake shelters performing animal control can replicate these results.