Functional polymers with well-defined architectures, molecular weight distribution, and precise location of the functional groups are of utmost importance in modern polymer research and neighboring disciplines. Despite the versatility and amplified tolerance to most functional monomers, living/controlled polymerization techniques suffer from difficulties when it comes to creating a library of functional polymers with identical degree of polymerization and functional group distribution, highly essential for their structure-property relationship studies. In this regard, post-polymerization modification offers a beneficial alternative approach for tailoring multifunctional macromolecules by introducing the dissenting functional group after the polymerization step. However, it requires a highly efficient chemical reaction on a polymer chain to ensure near quantitative installation of functional units. As many chemical reactions have been introduced for post-polymerization modifications, many of them begin with polymer chain containing reactive site. The sequence of functional monomer synthesis, polymerization, and functionality transformation is a general approach. If we could directly install functional groups into a commodity polymer, it would ultimately desirable. Our research group is recently investigating a direct transesterification of poly methylacrylate with a range of alcohols of interesting structures. The development of reaction system and its current status will be presented.