There are several options of representation of interests in court:
1. If you represent your interests in the process as the plaintiff or the defendant (personally). This is typical of civil litigation. And personal involvement in the process, does not preclude your right to have the court representative in the case.2. If you represent the interests of individuals or legal entities (person or organization). For this you will need a special power of attorney executed and authenticated in accordance with the law. According to the law by the representative in court can be a capable person, whose powers are documented properly.
So, the power of attorney must be executed in the notary office. Any organization that currently operates your trust; or the administering organisation at the place of residence of the principal; or public health institution, if the principal is on treatment or examination; the commander, if the Trustee passes the military service; and even the warden, if the Trustee is serving a sentence in places of deprivation of liberty.
After registration of the relevant documents, you, as representative, will have the right to perform all procedural actions. But special powers such as the transfer of power of attorney to another person, filing a new claim or the conclusion of a settlement agreement in the case should be specially stipulated in the power of attorney issued by the person you represent.
You can also go to court with the requirement about compensation of expenses for representative, if you are the principal. You will need to submit a contract for the provision of such services and the receipt that the representative received money as payment.
But there are some differences when it comes to representation in criminal proceedings. Here the features: the defender of the accused can become a lawyer, one of the relatives of the accused or another person for which the accused seeks.That makes all the difference. In any civil proceedings a representative can be almost any person, with a few exceptions prescribed by law.