The distribution of the focus particle even is constrained: if it is adjoined at surface structure to an expression that is entailed by its focus alternatives, as in even once, it must be appropriately embedded to be acceptable. This paper focuses on the context-dependent distribution of such occurrences of even in the scope of non-monotone quantifiers. We show that it is explained on the assumption that even can move at LF (e.g., Karttunen and Peters, in: Oh CK, Dinneen DA (eds.) Syntax and semantics, 1979). The analysis is subsequently extended to occurrences of negative polarity items (NPIs) in these environments, which mirror the abovementioned distribution of even and which invalidate standard characterizations of NPI licensing conditions in terms of downward-entailingness. The idea behind the extension is that NPIs denote weak elements that are associates of covert even (e.g., Lee and Horn, Any as indefinite + even, 1994). The paper concludes by discussing two comprehensive theories of NPI licensing and how our proposal relates to them.