Epithelial-mesenchymal transition (EMT) is a reversible and dynamic process proposed to be co-opted by carcinoma during disease progression and therapeutic refractoriness. The concept of EMT has evolved from a binary phenomenon of epithelial (E) and mesenchymal (M) states to a continuous spectrum, which includes intermediate hybrid E/M states. This continuous spectrum reflects the transition through multiple energy barriers which is similar to the concept of metastability in physics. The control of metastability could be demonstrated by regulatory networks involving the switches at the epigenetic and transcriptional levels resulting into the switches of functional phenotypes and signaling pathways. In this talk, I will also illustrate the genome-wide transcriptional and epigenetic landscapes including CpG methylations and histone modifications along the EMT spectrum and touch on the potential alterations of 3D chromatin architectures.