The nature of the crimes, particularly the last one, suggests professional terrorist involvement.

His professional involvement with opera began when he started writing opera reviews as a student, and it continues.

Although a highly respected film historian, Gifford's professional involvement in cinema was relatively limited.

His professional involvement with jazz was brief but controversial.

The memory of a time when American party politics was worthy of a writer's respect, let alone professional involvement, has almost disappeared.

Barbara's brown eyes, usually so filled with warmth and laughter, were sharp with professional involvement.

There also exist today two major areas requiring professional involvement in asset management and rehabilitation of existing buildings.

The aim of any professional involvement must always be to advise and assist parents in solving their own problems.

If self-help groups are not affiliated with a national organization, professional involvement increases their life expectancy.

Conversely, if particular groups are affiliated with a national organization professional involvement decreases their life expectancy.