meaning of the defence of equity; 
- the court may take account of and balance all factors affecting the relationship between the parites before deciding to order the restoration of or payment for the enrichment

-the overall equities of the case may mean that the enrichment stays where it is- even though all the positive requirements for recovery are met

- varney; it was ineq. to allow the builder to recover for the sewers it had installed instead of the local authority as 
1) parties had been in dispute about liabiltiy to perform
2) builder had had a remedy available at the time (action for implement of statutory remedy) =would have resolved