Different requirements apply to foreign jobseekers in Germany depending on where they come from.
Anyone holding a passport from an EU or EEA country or Switzerland enjoys freedom of movement for workers and freedom of establishment. Staying in Germany to look for a job is possible without restriction for up to 6 months without a visa or any other residence permit, as long as they can support themselves financially and have health insurance coverage.
Nationals of non-EU countries (third countries) always need a visa if they want to enter Germany to look for work. When applying at the German embassy or consulate, they already have to submit many other documents. In addition to a valid passport, these include proof of qualifications and, depending on the intended profession, the approval of the Federal Employment Agency (Bundesagentur für Arbeit) and a professional license, if applicable.