L'estro armonico (the harmonic inspiration) was published as Antonio Vivaldi's Op. 3 in Amsterdam in 1711. Vivaldi's Opp. 1 and 2 had only contained sonatas, thus L'estro armonico was his first collection of concertos appearing in print. It was also the first time Vivaldi chose a foreign publisher, Estienne Roger, instead of an Italian. Vivaldi composed a few concertos specifically for L'estro armonico, while other concertos of the set had been composed at an earlier date.
The concertos belong to the concerto a 7 format, that is: for each concerto there are seven independent parts. In each consecutive group of three concertos, the first is a concerto for four violins, the second for two violins, and the third a solo violin concerto. The cello gets solistic passages in several of the concertos for four and two violins, so that a few of the concertos conform to the traditional Roman Concerto grosso format where a concertino of two violins and cello plays in contrast to a string orchestra. L'estro armonicopioneered orchestral unisono in concerto movements.