  Most fairness assumptions used for verifying liveness properties are
criticised for being too strong or unrealistic. On the other hand, justness,
arguably the minimal fairness assumption required for the verification of
liveness properties, is not preserved by classical semantic equivalences, such
as strong bisimilarity. To overcome this deficiency, we introduce a finer
alternative to strong bisimilarity, called enabling preserving bisimilarity. We
prove that this equivalence is justness-preserving and a congruence for all
standard operators, including parallel composition.
