To create a more convenient analytical system for the determination of hormones in human serum, we attempted to make a robotic system by combining robotic equipment and the DELFIA system (time-resolved fluoroimmunoassay; Pharmacia Co.). To combine the two systems, we constructed various peripheral instruments, created software for the computer, and introduced these to the robot at our laboratory. We developed this system to operate more exactly and smoothly than manual procedures during analytical movement steps such as taking samples, adding reagents, mixing samples in kit strips, and measuring the results of the fluoroimmunoassay. With this system the robot can measure in random sequence eight hormones--thyrotropin, triiodothyronine, thyroxin, prolactin, lutropin, follitropin, choriogonadotropin, and cortisol--according to physicians' orders placed through the computer. Consequently, this robotic system can operate fully automatically, from delivering the samples into the robotic system to printing out graph reports for physicians. The technologist merely puts the sample rack on the conveyor belt.