Bröckers is also a long-time activist and author advocating the legalization of hemp.[citation needed] In 1993 he co-authored the influential Die Wiederentdeckung der Nutzpflanze Hanf (The Rediscovery of the Agricultural Crop Hemp) with Jack Herer. His Albert Hofmann und die Entdeckung des LSD (the Discovery of LSD) was published in Jan. 2006.[citation needed] He has spoken at conferences promoting the use of LSD.[citation needed]