Certainly, overactive autoimmune response can be a tricky business, among other challenges.

Assessing the roots behind any supposed national trait is a tricky business.

A tricky business this, as there are plenty of factors to consider.

Expanding a retail business into another geography is a notoriously tricky business.

Visiting favourite TV series from one's youth is always a tricky business.

Picking the follow-up to a major hit is a notoriously tricky business.

Batting may continue to be a tricky business if these conditions prevail throughout.

This was a delicate business, a tricky business, a confusing business.

Online dating is a tricky business at the best of times.

Facelifting can be a tricky business for volume car makers, especially with best-sellers.

It's a tricky business, trying to get away with this sort of thing.

Joining a human being with a darkling is a tricky business.

Awarding something as subjective and nuanced as music is inevitably a tricky business.

Buying and renting property around the world is a tricky business.

Keeping subjects in a major study is a tricky business.

Marriage is a tricky business at the best of times.