Abstract: Provided is a single construct combining a sequence encoding an RNAi molecule, a sequence encoding a reporter, and a target sequence specific for the RNAi molecule. The construct can be used to determine the potency of the encoded RNAi molecule in a direct and unbiased way. These results can be used to inform the design of potent RNAi molecules of various types and can be extended to several other applications, including: (1) generation of tiled libraries comprising every possible RNAi molecule-encoding sequence for a given gene target; (2) large-scale parallel validation of RNAi molecules targeting many genes to generate validated RNAi molecule-encoding libraries; (3) experimental comparison of design algorithms and strategies; and (4) investigation of RNAi biology in target site mutagenesis assays by screening pools containing single nucleotide changes in target sites and/or in the RNAi molecule to identify the most relevant sequence characteristics of potent RNAi-target site predictions.