Abstract: The present invention relates to compositions and methods for detection and quantification of individual target molecules in biomolecular samples. In particular, the invention relates to coded, labeled probes that are capable of binding to and identifying target molecules based on the probes' label codes. Methods, computers, and computer program products for identifying target-specific sequences for inclusion in the probes are also provided, as are methods of making and using such probes. The probes can be used in diagnostic, prognostic, quality control and screening applications.