Arguably the most important systematic theology ever produced in the Reformed tradition – I have found it to be the most valuable. – Richard Gaffin

From the Publisher:

“In partnership with the Dutch Reformed Translation Society, Baker Academic is proud to offer in English for the very first time all four volumes of Herman Bavinck’s complete Reformed Dogmatics. This masterwork will appeal not only to scholars, students, pastors, and laity interested in Reformed theology but also to research and theological libraries.

Includes:
Volume 1: Prolegomena
Volume 2: God and Creation
Volume 3: Sin and Salvation in Christ
Volume 4: Holy Spirit, Church, and New Creation ”

From J.I. Packer:

“Bavinck’s Dutch masterwork was the Everest of which the textbooks by Louis Berkhof and Auguste Leoerf were foothills and Berkouwer’s studies in dogmatics were outliers. Like Augustine, Calvin, and Edwards, Bavinck was a man of giant mind, vast learning, ageless wisdom and great expository skill. Solid but lucid, demanding but satisfying, broad and deep and sharp and stabilizing, Bavinck’s magisterial Reformed Dogmatics remains after a century the supreme achievement of its kind.”

Get the 4 Volume set here.

Or, check out individual volumes:
Volume 1: Prolegomena
Volume 2: God and Creation
Volume 3: Sin and Salvation in Christ
Volume 4: Holy Spirit, Church, and New Creation

Also, there is a newly released abridged version: Reformed Dogmatics Abridged in One Volume

And, another popular digest of his 4 Vol. work written by Bavinck himself: Our Reasonable Faith