VOPA (vocal painting) is an extensive collection of interactive hand signals developed by Jim Daus Hjernøe (DK). VOPA is used to communicate non-verbally between conductor and singers to create improvisational vocal art. The system offers an advanced set of tools to lend shape and structure to the music of the moment. Both conductor and singers are able to implement live arranging, live composing, re-arranging, re-composing, use of contrasting elements such as shifting keys, modules and time signature etc. during a performance. It can also be used within traditional repertoire to convey details during rehearsals and live in concert.

VOPA has its roots in Soundpainting (Walter Thompson, US) and is a vocal evolution of his original music sign language. In VOPA it has become a new language for vocal art, used to complement conventional conducting techniques of choral music. VOPA, a main tool in The Intelligent Choir methodology (Jim Daus Hjernøe), is currently consisting of 75 signals and more are in the making. The signals are easy to understand and the conductor can use them to adjust the musical expression within every desired musical parameter. Through the development of VOPA, as a pedagogical tool and an artistic methodology, the signals have shown to be surprisingly effective as an easy and fast way to create music with singers of all levels, from audience participation to the highest professional level of vocal arts.