What are benefits of foreign workers for the supplying country?

When people leave their home country to work in another country, their home country benefits in two main ways. 

First, the home country benefits because workers in foreign countries tend to send money back home.  This money that they send back is usually known as remittances.  As you can see in the links below, some countries depend very heavily on remittances for their national income.  The home economy is not very strong, so it benefits greatly when people go work in foreign countries and send part of their wages back to their relatives at home.

Second, the home country benefits because the workers take some pressure off the home country when they leave.  If all those workers stayed home, they might be angry about lack of jobs and about the problems of their country.  Their pent-up anger might help cause social unrest.  When they leave the country, there are fewer people competing for jobs in the home country, making for less anger among the people who remain at home.

In these two ways, foreign workers benefit the country that supplies them.