You have selected Communications-Based Train Control (CBTC) for your new transit line, or as an upgrade to the signaling system on your existing rail network. You look forward with anticipation to the benefits it will bring your agency in terms of capacity, safety and reliability. You plan to release your Request for Proposals to the street and then sit back and watch a pack of ravenous CBTC system suppliers pounce on it, eager to make all your signaling dreams come true. But how do you ensure consistency among the offers, to enable you to select the right system for your operation? How do you specify a system that can reasonably be delivered within your budget and schedule constraints? Should you evaluate based on capital or life cycle cost? What bid evaluation criteria should you employ? There are so many factors to consider: tried and true technology vs. cutting edge; an off-the-shelf solution vs. one customized to the exacting specifications of your Operations and Maintenance departments; the degree to which redundancy should be built into the system; readiness to integrate with other support systems, like the data communications backbone or SCADA. Is one CBTC system architecture a better fit for your property, or is it “six of one, half a dozen of the other”? This paper will address the technical components of these factors, to assist you in selecting the right technology for your CBTC deployment.