“Pied‐piping” has been viewed throughout the evolution of generative grammar as involving the displacement of a constituent that is larger than, and properly contains, the element the particular movement operation is normally targeting (such as a
wh‐
word contained within some larger phrase, e.g.,
which (boy)
/
whose
in
which boy's father/whose friends
). Being an effect directly associated with movement operations, its status and accounts have undergone significant shifts in the course of the evolution of the theory of grammar. The chapter provides a comprehensive overview of pied‐piping phenomena and discusses proposed analyses along with the theoretical contexts in which they arose. It lays out the variety of pied‐piping effects and central generalizations observed in the literature of the past decades regarding what pretheoretically can be considered pied‐piping structures. Starting with Ross' Pied‐Piping Convention, the chapter critically assesses the status and treatments of (apparent) pied‐piping, from Ross’ stipulation of a split between what triggers movement and what size constituents end up moving, via the Government and Binding model's “feature percolation” mechanisms and “Move α,” to potential accommodation of pied‐piping effects within the Minimalist Program's restrictive framework, relying only on projection, not feature percolation crossing maximal projections, and on “Agree.” The chapter delineates the descriptive dimensions of pied‐piping primarily based on
wh
‐movement. It examines attested construction‐specific variation – namely,
wh
‐pied‐piping in restrictive and non‐restrictive relative clauses,
wh
‐questions, and free relatives – and explores structural properties of the phenomenon such as the phrase‐internal position of the pied‐piper, the category types of pied‐piped phrases, and non‐
wh
‐pied‐pipers. The related theoretical issues assessed include the locality/structural limitations on what can induce a pied‐piping effect, the “repair” nature of pied‐piping, the status of marked “massive” pied‐piping, and attested parametric variation. The chapter discusses feature percolation approaches and outlines two recent alternatives dispensing with the latter within a minimalist perspective.