In this thesis, we shall examine a strong form of Oka’s Lemma which provides sufficient conditions for compact and subelliptic estimates for the d-bar Neumann operator on Lipschitz domains. On smooth domains, the condition for subellipticity is equivalent to D'Angelo finite-type and the condition for compactness is equivalent to Catlin’s condition (P).
Once the basic properties of this condition have been established, we will study the extent to which these estimates can be extended to higher order derivatives on C^k domains, with k greater than or equal to 2. For the Lipschitz case, we will look at higher order estimates in the special case when the domain admits a plurisubharmonic defining function.
Finally, we will use these estimates to construct a compact solution operator for the boundary complex.