Seebold joins from Research International and Mark Cutter joins as senior research executive from Synovate.
Adele Gritten, director and head of the media team, said: "These appointments take the media team to 10 people and reflect the pace at which this sector is growing for us."
Seebold has more than 12 years' experience in market research in the UK and Australia, starting at TNS. He will be working closely with Gritten to develop quantitative research within the media team. Cutter also has extensive media and communications experience, including telecoms.
Quaestor was established in 1986 and is now one of the fastest-growing research agencies in the UK with turnover in excess of £6m. It operates in three sectors: financial services, consumer, and media and broadcasting, which is headed by Adele Gritten.
Recent clients include HBOS, Channel 4, Otto UK, JCDecaux, NTL/Telewest, Prudential Assurance, Pataks and Scottish Power.
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