Ener conservation comprises an important element in environmen tall-conscious (green) engineering. In a Southeas-tern city, there are 310 traffic intersections that have been converted from incandescent lights to light-emitting diode (LED) lights. The study that led to this decision was conducted by the sustainability manager of the city. The wattage used at the resultant lighting bill has been lowered from $440,000 annually to $44,000 annually. When engineers went to check the traffic light meters for the fist time,they were shocked by the low wattage numbers and the associated cost. One of them said,"We thought the meters were broken because the reading were so law. "The annual savings of $396,000 per year from the traffic light conversion more than paid for $150,000 cost of installing the LED lights. Chapter 1 in troduces students to the decision-marking process that accompanies "go/no go" evaluations of investments in engineering projects such as the one described above.