In addition to Barenreiter's scholarly-critical editions of Brahms' trios, an arrangement of Brahms' String Sextet op. 18 for piano trio by his contemporary and friend Theodor Kirchner is now being published. Simrock, Brahms' publisher, issued it in 1883. Brahms responded to the arrangement of his sextet with total enthusiasm and praise for the skills of his friend Kirchner.
Christopher Hogwood's scholarly-critical edition includes an introduction which sheds light not just on the history of the arrangement and its validity in its own right, but also on Kirchner and his relationship to Brahms.