Complex coacervation is an associative liquid/liquid phase separation resulting 
in the formation of two liquid phases: a polymer-rich coacervate phase and a 
dilute continuous solvent phase. In the presence of a third liquid phase in the 
form of disperse oil droplets, the coacervate phase tends to wet the oil/water 
interface. This affinity has long been known and used for the formation of 
core/shell capsules. However, while encapsulation by simple or complex 
coacervation has been used empirically for decades, there is a lack of a 
thorough understanding of the three-phase wetting phenomena that control the 
formation of encapsulated, compound droplets and the role of the viscoelasticity 
of the biopolymers involved. In this contribution, we review and discuss the 
interplay of wetting phenomena and fluid viscoelasticity in coacervate/oil/water 
systems from the perspective of colloid chemistry and fluid dynamics, focusing 
on aspects of rheology, interfacial tension measurements at the 
coacervate/solvent interface, and on the formation and fragmentation of 
three-phase compound drops.