The role of DNA helicases in promoting progression of DNA replication through sites that are difficult to replicate is of particular importance for our understanding of maintenance of genomic stability. During each cell cycle, DNA replication needs to overcome multiple obstacles, such as DNA-bound proteins, DNA secondary structures, and damaged DNA. The goal of our research is to understand how the Pif1-family of helicases, conserved from yeast to metazoans, aid DNA replication across barriers in general, but particularly at telomeres, which are known to impede replication and whose integrity is fundamental to genome stability.