The short answer is: not always.
Let’s be honest. Translation can be expensive, and buying translation services can be confusing. There are times when you need a trained, experienced, credentialed translator. And there are times when you don’t.
Say your Indonesian client sends you an email in English, but the email is part of a chain of emails whose content you need to read, and the client didn’t give you a summary or explanation of the content of those emails. In this case, machine translation engines (which is the official term for Google Translate, Microsoft Bing, Babelfish and others), will be extremely helpful. You don’t need to know the exact content; it doesn’t have to be a perfect, award-winning translation. You just need to get the gist of what’s being said.
But let’s say that this chain of emails is part of a case involving a company and a foreign subsidiary, and the document will be filed in court. The court will require a certification. You can hire a competent translator, ideally with both translation training and experience, and subject-matter knowledge, if the topic of the emails warrants it. This person can provide a notarized certificate of accuracy, which you’ll need for your court filing.
Wait, you say. I don’t know any Indonesian translators. I don’t even know where to look for one, much less a competent, experienced one that is well-versed in the required subject matter. Here’s where an agency can help.
Then there are the times when a translator is not enough. For example, a corporate restructuring case involving creditors in several different countries requires translation of key documents into several languages. Or a case involving a Brazilian company is being tried in federal court, and there are hundreds—or even thousands—of discovery documents to be translated from Brazilian Portuguese to English. A single translator, or even a team of translators in the first example, could handle the work. But if you don’t have access to translators, if you don’t have the time to coordinate the project, or you need a very fast turnaround, an agency will be your best bet.