The main governing body of the American Crystallographic Association is the Council. The Council, which meets two to three times per year, sets policy and has the ultimate responsibility for the actions of the association. It is composed of a president, vice president, Canadian representative, secretary and treasurer. The membership elects these officers and each serves a three-year term, commencing on January 1st.

Ex-officio members appointed by the Council are the Chief Executive Officer and Chief Financial Officer. A representative of the Young Scientist Scientific Interest Group is also an ex-officio member. The YSIG makes this appointment on an annual basis. A representative from the International Union of Crystallography may attend Council Meetings but has no voting privileges.


2021 ACA Executive Council Members: 

Department of Biology | University of Waterloo
 Vice President:
Diana R. Tomchick
UT Southwestern Medical Center | Departments of Biophysics & Biochemistry
Immediate Past President: 

Advanced Photon Source | Argonne National Laboratory

Canadian Representative:
Department of Chemistry | York University

University of Pennsylvania

Ilia A. Guzei
University of Wisconsin-Madison

2021 Council Appointments

YSIG Representative: 

Chelsy Chesterman 



IUCr Representative:

Thomas Proffen

Neutron Scattering Sciences Div, Oak Ridge National Lab

Executive Director:

Kristin H. Stevens

 US National Division

President 2021

Tamir Gonen 

University of California, Los Angeles


Secretary/Treasurer 2021

Eric Reinheimer


2020 Non-Council Appointments 

RefleXions Editor:

Paul Swepston


Virginia Pett

ACA/AIP Representatives  

Member of AIP Publishing’s Board of Managers & Publishing Partnerships Committee:

Thomas Koetzle

Member of AIP Publishing’s Publishing Partnerships Committee:

Charles Carter

ACA Member of the AIP Board of Directors:
    ACA Representatives to AIP Liaison Committees
    ACA Representative to the AIP Liaison Committee on Underrepresented Minorities (LCURM):
    Krystal McLaughlin (Term Ending 2021) 
    ACA Representative to the AIP Liaison Committee
    Miriam Rossi (Term Ending 2022)

    ACA Representative to the AIP Liaison Committee on Public Policy (LCPP)

    Steven Sheriff (Term Ending 2022)

    Kraig Wheeler (Term Ending 2022)
    Structural Dynamics 


    Prof. Majed Chergui

    Structural Dynamics Board of Managers

    Prof John R. Helliwell
    S.N. Rao
    Jason Wilde



    ACA Headquarters 
    Membership Secretary