Peste des petits ruminants (PPR) is an important viral disease of goats and sheep prevalent in West Africa and the Middle East. In recent years, PPR has emerged in India, first in the South India and later in North India. To study the genetic relationships between viruses of distinct geographical origin we have sequenced a 322 nucleotide cDNA fragment of the fusion protein gene generated using reverse transcription followed by polymerase chain reaction (PCR) amplification. Viruses from nineteen independent PPR outbreaks were compared; these included the prototype African strain from Senegal and viruses from disease outbreaks which have occurred at different times and locations across Africa, Arabia, the Near East and the Indian subcontinent. Four separate lineages of the virus were identified and the virus isolates from Asia over the past 2 years were all of one lineage which had not previously been identified in Africa or Asia.