Beta-decay spectroscopy provides a manner in which to determine the energy levels of daughter nuclei which may not be accessible with other techniques.  Information from these studies improves our understanding of nuclear structure properties which are needed as input to such widely varied areas as fundamental nuclear astrophysics and applied nuclear reactor design, where it is important to determine the generation of heat within a nuclear reactor core on short time scales.  However, there are significant limitations of our knowledge due to an inability to experimentally measure everything.  Therefore, it is necessary to rely on theoretical calculations which need to be vetted with experimental results.  The purpose of this proposal is to perform detailed beta-decay spectroscopy measurements for a small number of nuclei to better understand the shortcomings of our current knowledge and how these shortcomings could be estimated for other nuclei.  To achieve this goal, we propose two primary activities.  First, the analysis of archival beta-decay data to extract additional information for all members of a decay chain.  Beta-decay spectroscopy measurements at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory produced data sets related to the specific parent nuclide of interest, but also for all members of the decay chain.  We have found that new and significant information can be found for the members of the decay chains closer to stability which were assumed to have been measured in detail previously.  Specifically, we have found discrepancies between our results and those in the Evaluated Nuclear Structure Data File (ENSDF) database compiled by the National Nuclear Data Center (NNDC).  We have finished the analysis of this data with several publications in preparation.  Second, the development of experiments to study specific properties of excited states fed by beta decay.  This includes level lifetime and conversion electron measurements to pin down spin/parity assignments. All experiments would utilize large-volume germanium detectors in close geometry to maximize efficiency providing gamma-ray singles and gamma-gamma coincidence data.  Ancillary detectors will be used to better resolve gamma rays with energies below 200 keV, to measure conversion electrons, and to measure level lifetimes depending on the nuclide to be studied. The Californium Rare Isotope Breeder Upgrade (CARIBU) facility at Argonne National Laboratory has a new beta-decay experiment station in a low background room which will allow for these types of studies.  Finally, proposals have been submitted to the Facility for Rare Isotope Beams (FRIB) at Michigan State University to use the FRIB Decay Station Initiator (FDSi) for several beta-decay studies related to the proposed research.  These experiments will generate a significant amount of data beyond that for the primary nuclides of interest, so data mining will be used to maximize the information that can be obtained from any one experiment.