Board & Executive
Rachel Tanny
Chair
Rachel Tanny
Rachel Tanny is the Chair of the Board of Parkinson’s NSW. She was appointed to the Board in November 2021.
Rachel has a successful track record in transforming and growing organisations. She is experienced in defining organisational strategy and translating it into measurable outcomes – as well as having a deep understanding of the aged care industry in Australia as it currently stands and forthcoming changes.
Rachel is a Graduate of the Australian Institute of Company Directors. She also holds a Diploma of Business Governance from the Institute of Community Directors Australia as well as a Juris Doctor from the University of Richmond.
Andy Esteban
Vice Chair
Andy Esteban
Andy Esteban was appointed to the Board of Parkinson’s NSW as an Independent Director in March 2023.He was appointed Vice Chair in March 2025.
He has been in the financial services industry for 45 years – including 21 years as National Manager, Trust Services for Perpetual Trustees, one of Australia’s premier funds management and trustee organisations.
Andy left Perpetual to establish F. P. Esteban and Associates – a risk and compliance service consulting to the broader funds management industry.
In addition, Andy sits as an independent Director and member of compliance committees and audit committees for a range of managed investment schemes (both retail and wholesale).
Andy holds a Bachelor of Business Degree (Accounting Major), is a CPA, a Member of the Executor and Trustee Institute and a Member of the Institute of Company Directors.
Dr Margaret Scott
Director
Dr Margaret Scott
Dr Margaret Scott was appointed to the Board of Parkinson’s NSW in November 2019 and President in February 2021 until November 2022. Previous Board positions include Fundraising Institute Australia (FIA), Australian Pet Welfare Foundation and Bloom Asia. She is a Fellow of FIA and has held international accreditation as a fundraiser, as CFRE, since 2002.
Margaret is highly regarded in Australia and internationally as a presenter, mentor and guide to individuals and organisations developing their fundraising skills and knowledge.
In staff roles, Margaret’s background included senior fundraising leadership roles in a variety of health and disability related not-for-profit organisations. In addition, she has operated her own business as a fundraising consultant since 2013 and since that time developed and presented fundraising training courses for teams, senior management, and Boards.
Margaret’s academic focus on fundraising leadership culminated in completing PhD studies illuminating the special relationship between CEOs and Board Chairs and the role of Boards in supporting and driving fundraising. Currently, Margaret tutors and supervises a number of students in industry and university learning programs.
Steve Schiemer
Director
Steve Schiemer
Stephen Schiemer was elected to the Board of Parkinson’s NSW in October 2018. He is a fitness instructor and entrepreneur who has been living with Parkinson’s for the past fifteen years.
In addition to experiencing Parkinson’s himself, Stephen runs tailored fitness programs for other people living with the disease.
He has a Bachelor of Business degree and 30 years of experience in running his own businesses, including finance, risk management, logistics, people management, training, and digital marketing.
Dr Martin Ostrowski
Director
Dr Martin Ostrowski
Dr Martin Ostrowski was elected to the Board in November 2023. He was diagnosed with Parkinson’s disease in 2017 and has a long family history with the disease. He has first-hand experience of the positive impact that education and integrated care can have on the long-term outcomes for people living with Parkinson’s and their families.
Martin is an active participant in several Parkinson’s NSW Support Groups. He is a regular speaker at the Parkinson’s NSW Newly Diagnosed workshops and recently initiated a support group on Norfolk Island. He recognises the importance of peer support and is committed to ensuring that people living in rural and remote areas have the same level of access to care.
Martin is an accomplished Marine scientist with over 20 years of experience working in the Tertiary Education sector. He is also Chief Science Officer of the Walking Tall research group, established to develop the Walking Tall mobile phone-based application. It is a gait re-training tool which allows people living with Parkinson’s to set their own training time and pace before delivering a rhythmic metronomic beat designed to trigger movement.
Mary Kay Walker
Chief Executive Officer
Mary Kay Walker
Mary Kay Walker joined Parkinson’s NSW in 2018 as Chief Operating Officer. In that role, she was responsible for delivering on the organisation’s services-led strategy by driving sustainable financial and operational performance.
Mary Kay brought this deep operational knowledge to the position of Chief Executive Officer when appointed recently.
Her priorities are contributing to the National Parkinson’s Action Plan, and advocacy to NSW Government Ministries and NSW Health. She is also strengthening relationships with researchers, Movement Disorder Specialists, and Parkinson’s nurses across the state.
Prior to joining Parkinson’s NSW, Mary Kay built a 32-year career in key finance and administration roles in Australia and the United States. She holds a Bachelor of Science with a double major in Mathematics and Bachelor of Science (Honours) in Psychology from the University of Sydney and a Diploma in Securities and Financial Markets from the Financial Services Institute of Australasia.
Mark Stewart
Chief Operating Officer
Mark Stewart
Mark Stewart joined Parkinsons NSW in 2023 and took on the Chief Operating Officer (COO) role in 2024.
Mark has spent over 20 years working in the not-for-profit sector in Australia, Europe and Asia as an executive level manager, after building a career in finance and accounting across a variety of industries.
His experience in driving transformation and growth through strategic and operational initiatives spans an extensive portfolio of organisations, with a focus on delivering superior leadership, stakeholder management and operational change to organisations with a strong values-based foundation.
Having been involved in organisational transformation from a board, executive and operational perspective, and with hands on experience in the operations, marketing, sales and fundraising areas, Mark is now bringing his experience to Parkinsons NSW.
Mark has previously served on the board and as chair of the audit & risk committee of WaterAid Australia, Pinnacle Foundation and is a member of the AICD.
