About Third Hemisphere
Third Hemisphere was founded by Hannah Moreno with a clear vision: to create a PR and communications agency that builds the kind of authority and trust that organisations need to grow.
From the beginning, Third Hemisphere has been drawn to brands building a better future. The technology companies solving problems no one else is solving. The sustainability ventures proving that commercial success and positive impact are not mutually exclusive. The founders who believe their work matters beyond their balance sheet. Working with impact-driven organisations is who we have always been.
Today, Third Hemisphere is a Certified B Corporation and an integrated PR, marketing and communications agency with offices in Sydney, Melbourne and Singapore. We are the Agency of Change: a communications partner for organisations that are doing something that matters, and need the world to know it.
Under Hannah's leadership and with Jeremy Liddle as Executive Chair, Third Hemisphere has grown into one of Australia's most respected boutique agencies for impact-driven and innovation-economy organisations.
By the numbers
- 150+ Clients Served
- 20,000+ Media Placements
- 64+ Years Combined Experience
- 3 Offices (Sydney, Melbourne & Singapore)
One story, every channel
- Media Coverage & PR Earned media placements across national, trade, and international outlets to build credibility and visibility.
- Video Content Compelling video assets for social, investor presentations, and brand storytelling that bring your narrative to life.
- Thought Leadership Bylines, opinion pieces, speaking engagements, and expert commentary that position your leadership as industry authorities.
- Social Media Strategic organic and paid social campaigns across LinkedIn, X, Instagram, and emerging platforms to amplify reach.
- Email & Newsletters Targeted email campaigns, investor updates, and newsletter programs that nurture relationships and drive action.
- Stakeholder & Partner Comms Tailored communications for investors, board members, government, partners, and other key audiences.
Leadership
Hannah Moreno
Founder & CEO
Hannah is our specialist author, editor, and social justice advocate, in charge of thought leadership for clients and Third Hemisphere. She has 20 years' experience across the gamut of communications disciplines, and has authored and placed hundreds of editorials for clients in Tier-1 media. This has included ghostwriting at the Australian Financial Review, and turning clients into official AFR Columnists. She is also a columnist at Stockhead and The Australian, and regularly contributes to Women's Agenda. Hannah holds a Bachelor of Commerce (USYD and Università Bocconi), a Masters of Strategic Public Relations (USYD), and a Diploma of Investor Relations (AIRA).
Jeremy Liddle
Executive Chair
Jeremy heads business development and strategy for Third Hemisphere as our capital markets, growth, climate, finance, and technology specialist. He is a founding partner of climate tech investment and advisory firm SDGx, has invested in 25+ tech and climate startups and multiple venture funds, and was President for Australia at the G20 Young Entrepreneurs Alliance. He also spoke at TEDx, authored the book "From Idea to Startup", and has worked extensively with the UN including co-authoring the G20 and UN white paper on youth entrepreneurship and participating in the formation of the Sustainable Development Goals (SDGs). Jeremy holds a Bachelor of Business (Monash) and a Graduate Diploma of Finance (Griffith).
Natalie Chua
APAC Lead
Based in Singapore, Natalie is APAC Lead, representing the firm's work across South East Asia. Natalie brings over a decade of experience advising multinational corporations, government agencies, and high-growth businesses across Asia-Pacific on strategic communications, reputation, stakeholder engagement, and commercial growth. Formerly Managing Director at Redhill Communications, she built and led a multi-million-dollar regional business and advised executive leadership teams on market expansion, strategic communications, and partnerships. She has delivered multi-market campaigns across Singapore, Vietnam, Hong Kong, Japan, Indonesia, and Malaysia, for brands in finance, real estate, FMCG, government, and technology.
Mark Xiaolin Lu
Director
Mark Xiaolin Lu is a Director at Third Hemisphere, based in Sydney, leading The Fourth Hemisphere, the agency's marketing for AI practice. He brings over 15 years in product and technology communications and B2B marketing across the United States, China, and Australia. Mark founded PrimaryCite.ai, an AI visibility consultancy helping technology and product brands become discoverable, compared, and trusted across AI platforms including ChatGPT, Claude, Gemini, Perplexity, and Google AI. Before that he was Chief Marketing Officer at food technology company 10% Plantech, and founder and CMO of Zhuzhang Tech, a digital merchandising and audience engagement platform where he acquired and managed over 100 enterprise and creator clients including GE, Lenovo, and Mercedes-Benz. Earlier he led integrated marketing and communications at CKGSB, one of Asia's leading business schools, and managed product and corporate communications, media relations, and PR at GE Energy China. Mark holds an MBA and a Bachelor of Arts from Rollins College, and works in both English and Mandarin.
Rachael Cassidy
USA Lead
Rachael Cassidy is USA Lead at Third Hemisphere, based in Oregon. She is one of the only Australians to have worked at the very top of the US PR industry, representing some of the biggest Australian and US technology brands. Most recently she was Executive Vice President and General Manager at Bateman Agency, leading global communications strategy, narrative development, executive thought leadership, and C-suite counsel across a multi-million dollar client portfolio. During her tenure the agency was named the San Francisco Business Times 2023 Fastest Growing Private Company in the Bay Area, ranking first on the FAST 100 list, the first PR firm to top it. Before Bateman she spent over six years at Mission North in San Francisco, rising to Senior Vice President and Corporate Reputation Practice lead, where she led communications for Snowflake's record-breaking NYSE debut and Ping Identity's IPO and built the firm's Corporate Reputation and Future of Work practices. She has counselled executives at Atlassian, Canva, Google Cloud, Gusto, Smartsheet, Workato, and 2U, and served as interim Head of Communications at Checkr. Rachael began her career in Australian broadcast journalism, anchoring live news as News Director at the Macquarie Radio Network and News Producer on Seven's Sunrise. She holds a Bachelor of Communications (Media) from Western Sydney University and a Graduate Diploma in Radio Broadcasting from the Australian Film Television and Radio School.
Team
- Mariam Imran USA, UK, EU, & MENA
- Isla Tweed Account Director
- Priyanka Dogra Senior Account Manager
- Marika Kishimoto Japan Lead
- Hanna Tiensuu Account Executive
- Veronica Robinson Account Executive
- KC Igna Operations Manager
- Vin Mendoza AI & Systems Manager
- Cath Casaway-Hormillosa Executive Assistant
Offices
- Sydney Level 3, 180 George Street
- Melbourne Level 27/101 Collins Street
- Singapore 160 Robinson Road, #14-04, Singapore Business Federation Center