Alexander Blum (Berlin) and Christian Joas (LMU) give a talk at the MCMP conference "Reduction and Emergence in the Sciences" (14-16 November, 2013) titled "From Dressed Electrons to Quasiparticles: The Emergence of Emergent Entities in Quantum Field Theory". Abstract: The development of renormalization group techniques and effective field theories in the 1970s have led to a major reinterpretation of the renormalization program originally formulated in the late 1940s within quantum electrodynamics (QED). A more gradual shift in its interpretation, however, occurred already in the early-to-mid-1950s when renormalization techniques were transferred to solid-state and nuclear physics and gave rise to the notion of effective or quasi-particles, emergent entities that are not to be found in the original, microscopic description of the theory. We study how the methods of QED, when applied in different contexts, gave rise to this ontological reinterpretation.