Citizens of certain countries who intend to stay for more than three months or to work in Germany may require a visa before arrival.Information about visa requirements can be found on the homepage of the German Federal Foreign Office (Auswärtiges Amt).
Citizens of the EU and EEA states, Switzerland, Australia, Israel, Japan, Canada, New Zealand, and the United States of America are exempt from the obligation to obtain a visa and may apply for a residence permit after entering Germany.
If your spouse wishes to travel to Germany with you, he/she will usually be granted the same rights of residence as you have. This right will expire when your own right of residence expires.
A residence permit for a spouse will usually be granted if it is apparent that the subsistence of both partners is assured without the need for social welfare support and these have adequate living space and health insurance cover.
Under the law as it stands, children only have a legal right of residence in Germany if both their parents have a residence permit, the child has not yet reached its 16th birthday, and in case its accommodation and financial support are suitably provided for. In other cases, the Foreigners' Registration Office (Ausländerbehörde) will make a decision at its own discretion.