1. Is there an analogue of the Lyndon–Hochschild–Serre spectral sequence for a non-normal subgroup? 2. What can you say about it? Can you describe $E^{p, q}_1$ ? What is about $E^{p, q}_2$? 3. What is the best technique to get the spectral sequence? For me the Grothendieck spectral sequence us much better than the spectral sequence of a filtered complex. There is a parallel question which is likely easier. 1. Is there an analogue of the Hochschild–Serre spectral sequence for a Lie subalgebra which is not an ideal? 2 and 3 remain the same. I already asked [a version of this question on MathSE](https://math.stackexchange.com/questions/1112179/) but got no responses.