The Universe of Alternatives screening process began with an initial pool of potential alternatives for transit improvements that were identified from a review of the existing conditions, plans and previous studies. The goals, objectives and evaluation criteria will play a role only as guidelines in this preliminary step, since the alternatives will not be technically evaluated in detail. Those alternatives that are similar among themselves; as well as the alternatives that can not be built by physical, environmental or financing limitation are discarded. Twelve alternatives were developed to provide transit service between the municipality of Hatillo and the municipality of Bayamón. While these alternatives serve the same basic corridor, they are different from each other. The divergence consists of transit technologies, alignments, station locations and operational characteristics.