Dear construction chemists,

On the occasion of the 3rd International Conference on the Chemistry of Construction Materials - 3rd ICCCM for short - I was able to take advantage of the coronavirus pandemic for the first time: I was able to take part in the online members' meeting of the specialist group. I certainly wouldn't have travelled to XY. Even if this medium doesn't allow for many things, this contact is better than no contact at all.

For me, it was also a look back at the beginning of the Construction Chemicals specialist group. I have fond memories of that time.

At the beginning, it was the initiative of the GDCh management, represented by Dr Behret. They invited me to the GDCh office in Frankfurt for exploratory talks

the industry/ "Deutsche Bauchemie", Mr Schröter and

the scientific community/ represented by me.

At first, Mr Schröter and I were somewhat hesitant to take up the GDCh initiative. But it took off. Through meetings, assemblies of GDCh members interested in construction chemistry in Frankfurt and elections, a "GDCh working group" was initially formed in accordance with the GDCh rules. I was elected chairman, probably in 1994, and the "Deutsche Bauchemie" was initially extremely sceptical about this. For example, Dr Behret and I were invited to Altötting by the then chairman of "Deutsche Bauchemie", Mr Poech, for a discussion. The discussions could not prevent us from being founded, and we did not allow ourselves to be deprived of the designation "Bauchemie" in our name, which the inviting party did not want.

In November 1996, the working group organised its first event, a workshop in Hünfeld near Fulda. Even then, I made sure that the presentations were printed in a citable form. The first conference proceedings were published (GDCh monograph vol. 7). This remained the case during my time and beyond. We did not yet have an impact factor. We assessed the scientists according to more general criteria. The points system only came later, perhaps from football?

In 1997, we were "promoted" by the GDCh from a working group to a specialist group. We had probably done a satisfactory job. The new board members were: Prof Dr Knöfel (University of Siegen; chairman), Prof Dr Hummel (Knauf Gips; deputy chairman), Dr Akstinat (Holderchem, CH), Prof Dr Cammenga (TU Braunschweig) and Prof Dr Hiller (TU Munich). The awareness of the specialist group increased. The number of members increased to over 300, as reported by the current group chairman Dr Frank Winnefeld at the 2021 general meeting (at some point). We organised three conferences (1997 in Munich, 1999 in Siegen and 2001 in Würzburg, correspondingly three conference proceedings/GDCh monographs vol. 11, vol. 15 and vol. 24 were published under the title "Construction Chemistry - from Research to Practice". I retired in the summer of 2001 and my time as chairman ended in the autumn of the same year. I had capable colleagues in all areas, to whom I am greatly indebted. For me, it was a fulfilling time that I look back on fondly.

The train was set on the track, it was rolling. The train driver was changed, Prof Dr Cammenga arrived and others followed, successfully leading the specialist group to the present day. Firstly, I would like to thank everyone whose work has maintained and expanded the success of the specialist group over the past few years. First and foremost, of course, I would like to thank the members of the Executive Board over the past five terms - with their chairmen at the helm. Five electoral terms - 20 years - that's how long ago I retired from active involvement.

Of course, the Executive Board cannot function without active members, which is why I would like to fully recognise and thank the many members whose contributions are what make the specialist group so special. I wish the specialist group a continued successful future.

Children have a father, sometimes several fathers, sometimes none. In our Construction Chemicals specialist group, none of the fathers involved will want to deny their involvement. There were many fathers and everyone will look back on their children and grandchildren and their work with gratitude and a little pride.

Dietbert Knöfel
Berlin, 16 March 2021