Commerce is a branch of production which deals with the exchange of goods and services from producer to final consumer. It comprises the trading of something of economic value such as goods, services, information or money between two or more entities.
Commerce primarily expresses the fairly abstract notion of buying and selling, whereas trade may refer to the exchange of a specific class of goods (“the sugar trade”, for example), or to a specific act of exchange (as in “a trade on the stock-exchange”).
Business on the other hand, can reference an organization set up for the purpose of engaging in manufacturing or exchange, as well as serving as a loose synonym of the abstract collective “commerce and industry”.
http://en.wikipedia.org/wiki/Commerce

Business is not really needed...


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Note added at 13 hrs (2007-09-07 12:09:32 GMT)
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I agree with the examples above but they are also part of wider concepts. Used on its own, especially as a subject, it sounds a little odd to the native ear. Business sounds superfluous.

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Note added at 5 days (2007-09-12 14:00:03 GMT)
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It depends on context (doesn't it always?!) but business to my mind is more generic than trade. Thin of business as the overarching concept and trade as something more concrete. Hope that perhaps helps.

Prema Hrvatsko-Engleskom rijecniku,M.Drvodelic