Sound and complete equational theories for divergence sensitive variations of weak bisimulation semantics have been
studied in the past. Taking van Glaabeek's "linear time - branching time spectrum with silent moves" as a
reference, only for one of them no complete equational theory has been known so far: strongly convergent weak
bisimulation preorder. My Master's thesis closes this gap by providing a sound and complete equational theory of
strongly convergent weak bisimulation preorder. As a side result, the thesis also fixes a flawed completeness proof for an
equational theory of convergent weak bisimulation preorder, first published by Walker in LICS '88. In this talk, I will give a
survey of this research area and present the results of my thesis together with a bird's eye view of the completeness
proofs.