The American Crystallographic Association proudly announces the Class of 2025 ACA Fellows—an exceptional group of scientists whose groundbreaking research, impactful teaching, and dedicated service have shaped the field of crystallography and structural science in profound ways. This year’s honorees represent a remarkable spectrum of contributions, from advancing foundational methods and developing revolutionary technologies to championing education, mentoring, and equity across the global scientific community.

Please join us in congratulating:

The American Crystallographic Association proudly recognizes three outstanding scientists whose work is advancing the frontiers of structural science:

• David G. Rognlie Award – Dr. Yifan Cheng (UCSF): For transformative innovations in cryo-electron microscopy, including motion correction algorithms and atomic-resolution structures of membrane proteins like TRPV1. His work helped launch the "Resolution Revolution" and continues to drive the field forward.

• A.L. Patterson Award – Dr. Randy J. Read (University of Cambridge): For pioneering likelihood-based methods in macromolecular crystallography, including the development of σA maps and Phaser software—tools now central to modern structure determination.

• Margaret C. Etter Early Career Award – Dr. Emmanuel Nji (CRID, Cameroon): For groundbreaking work on membrane transporters and leadership in building structural biology capacity across Africa through BioStruct-Africa.

Each year, the American Crystallographic Association honors individuals who are pushing the boundaries of structural science. In this post, we’re thrilled to introduce the 2026 ACA Award winners—three exceptional scientists whose innovations and leadership are making a global impact. These awards will be formally presented at the IUCr2026 Congress in Calgary; details of the ceremony will be announced in the coming months.

The U.S. crystallographic community is undergoing a critical transformation. Since 2018, when the National Science Foundation (NSF) designated crystallography a “mature” field and ceased direct support for the U.S. National Committee for Crystallography (USNC/Cr), the committee has been sustained by private donations, a single NIST grant, and careful budgeting. This patchwork funding model, however, has proven unsustainable. For example, NAS is paid for its services and has not kept pace with basic USNC/Cr management responsibilities, such as updating committee appointments, maintaining its public website or interacting with IUCr.

The situation has become more urgent following recent communications from Ourania Kosti at the National Academy of Sciences (NAS), indicating that NSF will no longer delegate stewardship of U.S. National Committees to NAS. Instead, a new centralized framework will place oversight under NSF or a new federal entity. Critically, crystallography is not among the disciplines included in this transition. As a result, the USNC/Cr is at risk of losing both structural support and federal recognition for the 2025–2029 cycle. Furthermore, Ms. Kosti is going to recommend to the NAS Council in early August that NAS cease to be the adhering body to the IUCr for the U.S.

As I’m writing this column for our summer newsletter, we are rapidly approaching our 75th annual meeting in Lombard, IL. The meeting committee and headquarters team have been working overtime to get everything in order, and to make it a fantastic celebration of our community. I would like to extend a personal pre-emptive thanks to everyone involved, from our Meeting Committee, headquarters team, session chairs, speakers and poster chairs who are all contributing to make our annual meeting one with something for everyone.

You may be curious as to why this newsletter is unlike previous editions of RefleXions. As was mentioned in our Spring newsletter, our long-time editor of RefleXions, Paul Swepston, has stepped back from this important role. Thank you, Paul, for all your work and commitment to the ACA. We are moving forward into a more digital-style newsletter, and we hope that everyone finds it a fresh new platform to find out the latest developments in our Society. And while on the theme of connections and communications, I would like to remind everyone of the many ways to connect with our community through the ACA Video Library, History Portal, ACA Blog, Community Forum, and of course our society’s journal, Structural Dynamics. Please consider exploring and contributing to these important resources for our community.

On ACA Leadership

By:  Christopher Cahill | Department of Chemistry | The George Washington University

What a thrill to be asked to share a few thoughts on leadership with the ACA community. In some respects, ACA provided me with my first ‘official’ leadership opportunity when I was elected to Council as Vice President in 2014. I had been leading a research group for about 15 years at that point, yet that was a very different experience, for sure. I felt drawn to the opportunity- ACA had been my scientific home for years, and some committee work had whetted my appetite for deeper engagement. I also felt that the ACA was then at a bit of a critical crossroads, and that I could contribute to re-tooling some aspects of operations. I was not explicitly aware of this at the time, but it turns out a strength that I have is to recognize the interconnected nature of challenges and opportunities, and to recognize what is important to a diverse group of stakeholders. As my leadership journey has continued, now to include Chemistry Department Chair for the past six years, I find that recognizing and acknowledging what is important to people, and then advocating for that within institutional constructs is rewarding and provides a wonderful sense of purpose.

As my career and experiences continue to evolve, I find myself feeling even more drawn to leadership and mentorship opportunities. My own interests have diverted away from the lab bench, and I enjoy living vicariously through my students, or through the junior faculty I am supporting. My predecessor in the Chair position at GW would always say ‘Your success is my success.’ And I could not agree more. Lately, I am most excited about helping create the infrastructure for others to do their best work, and I am motivated towards making processes and operations function more smoothly- it’s funny how the definition of a ‘win’ changes over time!

The ACA is proud to celebrate a major milestone in the career of Dr. James Kaduk, who has been elected a Fellow of the American Association for the Advancement of Science (AAAS)—one of the highest distinctions in the scientific community.

Jim’s impact on crystallography, particularly in the field of powder diffraction, is well known to our members. But beyond his scientific achievements, Jim has been a pillar of the ACA for years—a generous colleague, dedicated mentor, and tireless advocate for crystallographic education and outreach.

To Our Members and the Scientific Community:

As the leadership of the American Crystallographic Association (ACA), we remain steadfast in our commitment to the core values that define our organization: scientific excellence, integrity, inclusivity, and the free exchange of knowledge. In light of ongoing changes and challenges, we reaffirm our dedication to fostering an environment where science thrives, diverse perspectives are valued, and the highest standards of research and collaboration are upheld.

In Memoriam: George M. Sheldrick (1942–2025)

It is with profound sadness that the scientific community announces the passing of George M. Sheldrick, a pioneering crystallographer whose innovative contributions have left an indelible mark on the world of science. Born in 1942, George dedicated his career to advancing the field of crystallography, transforming the way scientists determine and understand molecular structures.

A Trailblazer in Crystallography

George’s groundbreaking work, most notably his development of the SHELX suite of programs, revolutionized crystal structure analysis. His methods brought unprecedented precision and efficiency to the field, empowering researchers across chemistry, biology, and materials science. Over decades, his innovations not only enriched academic research but also had practical applications in pharmaceuticals, nanotechnology, and beyond.

Spring is coming soon! Every year, on the 1st of April, the ACA collects nominations for its Fellows program. When I was elected a 2021 ACA Fellow, to be honest, I hadn’t put much thought into why professional organizations bother to make such distinctions. Certainly, being elected a Fellow is an honor and welcome recognition for any individual, but why do we, the ACA, The Structural Science Society, promote this type of recognition?

The professional world abounds with awards and honors designed to highlight specific scientific achievements, but the Fellows program is different. ACA Fellows are characterized as "scientific ambassadors" serving to advance the much broader goals of "scientific education, research, knowledge, interaction, and collaboration." Back when I was a student, my first inkling that science was more than just a single person "making discoveries" came when I started to realize that I needed collaborators. It was years before I fully appreciated all the elements that are required for science to advance and I'm still learning. Science is far more collaborative than I expected: experts with complementary skills must connect and build mutually beneficial relationships. New techniques need to be popularized and made accessible. Complex discoveries need to be communicated clearly and compellingly to engage the public and persuade policymakers of the value of long-term investments in science and education, despite their difficult-to-measure impact. Young scientists need opportunities to participate in and become part of a community ... and to understand the value of doing so.

Happy New Year ACA Members! 

As we step into an exciting new chapter, we’re thrilled to share some important updates and changes for the association.

Dear ACA Members:

As the holiday season approaches, it’s the perfect time to reflect on the power of community and the vital role we all play in advancing science. This year, I invite you to join the global #GivingTuesday movement, a day dedicated to generosity and making a positive impact.

Hello ACA Members,

A big thank you to everyone who shared feedback throughout the annual meeting in Denver and beyond! As your Executive Director, I’m committed to creating a safe and open space where all members can communicate and help make our association better. I want you to know that leadership is listening to your thoughts about communication within the ACA and is actively working to address these concerns. Stay tuned for more updates, but in the meantime, we’re starting to communicate a bit differently at HQ.

Introducing the ACA: Structural Science Society!

The American Crystallographic Association has a long and incredible history. Formed in 1949 by a merger of the Crystallographic Society of America and the American Society for X-ray and Electron Diffraction, the ACA promotes the study of the arrangement of atoms in matter. Even in the group’s first form, we wanted to offer a "home" for chemists, mineralogists, and physicists and now, more than fifty years later, the ACA is still evolving to welcome all structural science disciplines to the society.

Realizing that the ACA membership was growing to include non-crystallographers practicing structural science, in 2021 ACA Council voted to add “The Structural Science Society” as a tagline to the traditional ACA logo. This change prompted the search for a new logo that would better reflect all scientists determining atomic-scale structure, not only those practicing crystallography and established the ACA Logo Committee.

Hello Structural Science Friends! 

With the start of the new year we welcome a whole new group of ACA volunteers. The ACA is so lucky to have the most amazing and dedicated members who are always eager to volunteer in some capacity. Every year, when we elect and appoint new members to Council, Committees and SIGs, I am inspired by the enthusiasm and dedication demonstrated by these members.

Dear ACA Members, Colleagues & Friends:

Structure Matters! After several years with the ACA I can tell you that “structure” takes all forms. Most, in this group, are familiar with this term as it relates to the study of “the structure of matter at atomic (or near atomic) resolution” however, the ACA is also a structure. In terms of structure, the ACA is a strong association with a long history and a bright future. I am both honored and excited to take on the role of Executive Director and to join forces with such a passionate, dedicated group of members.