For nearly 20 years Questas Corporate has successfully acquired, operated and transformed niche industrial businesses across Australia.

Mark Taylor

Group Chief Executive Officer

Mark commenced as Group CEO with Questas Group in July 2018, and brings to the role 18 years of international finance and business experience in the mining industry.

Prior to joining Questas Group, Mark worked at Orica Limited. During his time at Orica, Mark held a number of senior leadership positions including General Manager Orica International based in Singapore, and Vice President Finance North America based in Denver. As VP Finance North America, Mark served on a number of joint venture boards.

More recently, Mark served as Vice President Finance for Orica in their Europe Asia Africa Mining Services division, based in Perth.

Mark is a qualified accountant (CPA) and holds an Executive MBA from University of New South Wales (AGSM). Mark is a Graduate of the Australian Institute of Company Directors.

Simon Carlyon

Group Chief Financial Officer

Simon joined Questas as Group CFO in June 2020 and has 25 years’ experience leading a variety of finance teams across a number of countries and industries.

Most recently prior to joining Questas, Simon spent four years with ASX listed healthcare group Healius, where he was the CFO of Pathology and a core member of the executive team, overseeing a national business with $1bn plus turnover.

Before joining Healius, Simon spent 10 years in the UK predominantly working in a variety of finance roles for FTSE 100 listed property REIT SEGRO plc, the last role of which was as Director of Finance. Prior to this Simon was at KPMG for 10 years, including 7 years in Sydney and 3 years in Chicago.

Simon has a Bachelor of Economics from Macquarie University and is a Member of Chartered Accountants Australia and New Zealand.

Steve Davis

Executive Director

Steve rejoined Questas in November 2013 as Chief Operations Officer before moving up in to the role of Executive Director in 2017.

Steve was previously employed within Questas Group, serving with Berendsen Fluid Power from 2001 to 2010 as their CEO and National Manager Branch Operations.

Prior to joining, Steve was employed with Tyco/Pentair Valves and Controls, holding the senior positions of Director of Service - Global Mining, and Director of Commercial Services – Pacific.

Steve also served with Capral Aluminium for 6 years in various operational and sales leadership roles. Steve is a member of the Questas Corporate, Water Dynamics and Malcolm Thomson Pumps Executive Committees.


James Leach

Chief Executive Officer

James joined the Berendsen Head Office team in 2008 as a Business Analyst working with Executive Management, the Branch network and Corporate in the development, testing and implementation of a range of business improvement initiatives covering a wide range of disciplines. In 2009 James moved into the role of acting Branch Manager in Wollongong before moving on to a similar role in Melbourne later that year.

Upon returning to Sydney in March 2010 James was appointed as National Manager Branch Development, holding responsibility for five branches as well as acting as Branch Manager for Adelaide. In addition, James was responsible for the management of BHA Imports and the National Customer Service Centre. Later that year James was appointed as CEO of Berendsen Fluid Power.

Prior to his employment with Berendsen, James held the role of Business Solutions Consultant with First Rand Bank Ltd, and Product Manager with Goldquest International Hydraulics, where he established Goldquest International Hydraulics Filtration Division. James holds a Bachelor of Commerce from University of the Witwatersrand as well qualifications in Project Management, and Advanced Hydraulics and Electro Hydraulics.

Kala Sonni

Group General Counsel

Kala joined Questas Group as Group General Counsel in February 2023. She has over 14 years of multijurisdictional experience leading mergers and acquisitions, corporate and commercial law, debt litigation and construction law litigation.

Prior to joining Questas, Kala spent over a decade as a Group General Counsel and Company Secretary for mining and resources goods and services provider VLI, where she was entrusted by the Private Equity shareholder to lead multiple acquisitions and establish a Legal Department. Before VLI, Kala worked for national law firms, including Moray & Agnew Lawyers, and ASX listed company, ACM Group Ltd.

Kala has a Bachelor of Laws (LLB), a Postgraduate Diploma in Legal Practice (PG.Dip Legal Practice) and a Master of Laws (LLM) from Bond University. She is admitted to practice in the Supreme Court and High Court of Australia.

Wayne McMahon

Chief Digital and Technology Officer

Wayne commenced in his role as Chief Digital and Technology Officer of Questas Group in July 2022. Wayne joins Questas with a strong history of transforming the IT function into a value-adding advantage for billion-dollar corporations across ANZ, Asia, and Europe.

Wayne has over 30 years’ experience of global and regional technology success, including the pioneering of many industry-firsts. Wayne has held CIO roles with the Super Retail Group, Domino’s Pizza Enterprises and Pizza Hut Australia, where he developed and lead multimillion-dollar delivery projects to drive revenue.

Throughout his career, Wayne has been focused on technology-led, whole-of-business transformations

Iain Read

Head of Acquisitions

Iain joined Questas Group as Head of Acquisitions in January 2020 and has 18 years’ experience in corporate finance and corporate development.

Prior to joining Questas, Iain spent three years with Wesfarmers Industrial & Safety, where he was a Senior Manager in the Commercial Team. Prior to Wesfarmers, Iain spent 11 years working in the investment banking industry for Macquarie Group and Greenstone Partners in the United Kingdom and Australia.

Iain has a Bachelor of Commerce and a Bachelor of Laws from the University of Adelaide and is a qualified accountant (CA).

Who We Are

Our Companies

We are a privately owned enterprise with diverse business operations in the following areas: