Diplomatic relations between New Delhi and Washington have been strained in recent weeks - not by political wrangling, but when an Indian diplomat working in the US was accused of underpaying her nanny. The episode has triggered a debate in India about the condition of millions of domestic workers. In all but two states, there are no labour laws regulating minimum pay, maximum hours, or official complaints channels. It's not uncommon to find cases of domestic workers being physically abused.
Our reporters went to meet some of these "Invisible Maids", as well as the campaigners calling for better rights.