Elastomers play a crucial role in the current society owing to their unique properties. Lately, revised versions of natural rubber, which are originally derived directly from plants, have been discovered to widen its scope of applications apart from tires and footwear. Natural rubber has a very limited range of molecular structures, which may narrow down its capacity to meet increasingly complex applications. Contrarily, several traditional synthetic elastomers possess a broader variety of molecular built and design and are used across various industries; however, they are predominantly derived from fossil-based non-renewable resources. Currently, most elastomers are largely non-recyclable due to the same reason. In addition to that, majority of them are thermosetting materials, thus challenging recycling and reusing. This eventually results in accumulation of plastic waste because it may take thousands of years to decompose, resulting in the formation of nano/microplastics, largely polluting the environment. This emphasizes the necessity to develop greener alternatives owing to their increased potential for controlling environmental pollution and addressing several sustainability concerns, further contributing to the sustainable advancement of the elastomer industry. This chapter discusses the sustainability in polymer elastomers by including a few methods and strategies for the preparation of bio-based elastomers. The primary objectives are to advance and enhance the synthesis, properties, and applications of bio-based elastomers derived from natural and industrial rubbers, polyurethanes, polyesters, and polyethers, while also addressing their circular economy and sustainability aspects. Bio-based elastomers are regarded to grow at an exponential rate in the coming decade. This chapter serves the purpose of providing an in-depth description of knowledge and critical aspects of bio-based elastomers as a greener solution for plastics, for a cleaner environment and its involvement in our modern society.