Natural or legal persons having either their residence or their principal place of business in a contracting state to the EPC can undertake all procedural steps before the EPO themselves and are not obliged to appoint a representative. Other applicants are, however, required to be represented by a professional representative (Article 134(1) EPC) or a legal practitioner (Article 134(8) EPC) (except when filing an application or paying fees).
Even if you are not obliged to appoint a professional representative, it may still be helpful to consult one. To make it easier to find what you need, the EPO maintains an up-to-date (updated twice a month) database of professional representatives. All you have to do is enter a search term or terms in one or more of the search fields and click the "Search" button.
This will generate a list of professional representatives who match your query. Click on a name to find details of the representative's full name, address, e-mail and website (where available). Click on the city or the country to view a list of all the professional representatives in that location.
The database is also accessible on the ESPACE LEGAL disc (updated twice a year), which offers more search options.