Telomeres in eukaryotes comprise specific repetitive DNA sequences and binding proteins. Since their absence results in chromosomal end fusions and gene deletions, they are considered critical for genomic stability. In plants, as in yeasts and mammals, telomeres are essential for normal development and differentiation. Despite recent discoveries concerning plant telomeres, many questions remain about the mechanism of telomere homeostasis in plants. In this review, we summarize the roles of telomeres and telomerasebinding proteins in plant biology and explain how the length of a plant telomere is regulated.