Perhaps the most important development in this regard is the opening of the internet. It has made the distance between colleagues who are continents apart seem trivial and their communication nearly instantaneous. Problems can be discussed through email, and graphs, diagrams, and pictures can be transported over the web. Conferences can be held among participants spanning the globe, and massive projects requiring multinational financial participation are routinely proposed. From the prospective of individual scientists, the world of science is already globalized.
Scientists routinely work together over the internet and exchange ideas, manuscripts, and data.
Science is now entering an era where experiments can be carried out by a scientist in one location on apparatus located half a world away. Real-time connection to the telescope will be provided by a broad band internet2 connection, so that scientists in widely distributed locations can participate in ongoing observations. In summary, science is a global activity. Individuals are not constrained in their collaborations by national borders, but only by commonality of interests. The credit, and blame, for this is due almost exclusively to the internet.