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In the last few years, Hubble Space Telescope (HST) imaging studies of a variety of extragalactic star-forming systems have identified a widespread new class of star clusters. The compactness and high luminosities of these objects, coupled with their inferred youth, have stimulated speculation that they represent present-day analogs of young globular clusters. Although the existence of a few such ``super star clusters'' (hereafter SSCs) had been known from previous ground-based studies (e.g., Arp & Sandage 1985; Melnick, Moles, & Terlevich 1985; Lutz 1991), it took the resolving power of HST to demonstrate the prevalence of this phenomenon. Such clusters appear to be found in a wide array of environments, ranging from nearby dwarf galaxies (O'Connell, Gallagher, & Hunter 1994; Hunter, O'Connell, & Gallagher 1994; O'Connell et al. 1995; Leitherer et al. 1996; Gorjian 1996), to more distant merging and interacting systems (Holtzman et al. 1992; Whitmore et al. 1993; Conti & Vacca 1994; Vacca 1994; Shaya et al. 1994; Whitmore & Schweizer 1995; Meurer et al. 1995), to circumnuclear star-forming rings (Benedict et al. 1993; Barth et al. 1995, 1996; Bower & Wilson 1995; Maoz et al. 1996a). In fact, as I will discuss later, it appears that the formation of compact clusters may be surprisingly commonplace in most regions of galaxies experiencing elevated levels of star formation, and need not be restricted to the most extreme starbursting environments.

This contribution will give an overview of the principal properties of SSCs, describe a new HST imaging survey and its applicability to the study of clusters, and summarize some recent work by my collaborators and myself pertaining to clusters in circumnuclear rings. I will also present evidence based on ground-based observations that at least some of the SSCs have dynamical masses resembling those of evolved globular clusters seen in the Galaxy.