The effects of globalization are both negative and positive depending on how you look at them.
One of the most obvious is outsourcing. Globalization encourages companies to move jobs from more expensive countries (e.g. USA, UK, Japan) to less expensive countries (e.g. China, Thailand, Guatemala). Many focus on the negative aspects of this: unemployment in the more expensive country, abuse of new workers, executive largesse. But there are positive aspects as well: lower prices for products, increasing values of investment securities, and more technical jobs.
Homogenization: the dissolution of ethnic differences. It can be negative due to the "death" of certain cultures. However, the "Melting Pot" of America demonstrates how adopting the best of different cultures and discarding the rest can strengthen cultures, and be the "birth" of new cultures.
Wage deflation: the negatives are obvious, but it can also encourage a lower cost of living by reducing the cost of production.