Telomeres are distinctive structures that protect the ends of linear chromosomes and ensure genome stability. They are composed of long tracks of repetitive and G-rich DNA that is bound by shelterin, a dedicated six-subunit protein complex. In somatic cells, shelterin protects telomeres from the DNA damage response and regulates telomere length. Telomere repeats are replenished by telomerase, a specialized ribonucleoprotein composed of telomerase reverse transcriptase and an integral RNA component. Telomere protection and telomerase regulation have been primarily studied in somatic cells. However, recent evidence points out striking differences in the context of embryonic stem cells (ESCs). In this review, we discuss insights into telomere protection in ESCs versus somatic cells and summarize findings on telomerase regulation as a function of pluripotency. TRF2 is dispensable for telomere protection in pluripotent cells. Loss of TRF2 in embryonic stem cells triggers a 2 cell-like stage. Alternative splicing promotes human telomerase reverse transcriptase (hTERT) mRNA accumulation in embryonic stem cells. Minor impact of hTERT transcriptional regulation as a function of pluripotency. [ABSTRACT FROM AUTHOR]