By dictionary, 'samadh'i is an 'ability' to concentrate on one subject at a time.

I find it increasing harder to keep focus on a subject especially when thee are many issues/interests/concerns involved. Nevertheless I've found that writing good articles (not for the sake of blogging) is a good way to develop smadhi.

I've also learned that 'sati' (keeping awareness of self and conditions of the enivironment I am in) is a complementary ability.

Samadhi keeps us on a narrow road and sati keeps our eyes open to the world around us!