OUR PRINCIPLES
Setting Standards for Responsible Decision Making
Our firm operates on principles that ensure independence, responsibility and professional integrity across all engagements. These standards guide our environmental approach, our analytical methods and the way we work with clients.
Independence
Independence is the organising principle of our advisory work. It protects judgment from external influence and ensures that analysis, assumptions and conclusions follow from facts and economic logic. We accept only those mandates where full independence can be maintained across the entire engagement.
Judgment
Recommendations are determined by evidence and decision logic rather than relationships or incentives.
Mandate Design
Engagements are structured to exclude conflicts. If independence cannot be preserved, we decline the work.
Boundaries
Advisory services remain distinct from legal opinion and representation, which are provided by partner law firms.
Accountability
Senior advisors own material decisions and are responsible for the integrity of the analysis and its consequences.
Equality
People and equal treatment define how we work. We maintain a safe, respectful and inclusive environment where opportunities, responsibilities and recognition are based on competence and contribution.
Dignity
Every interaction is conducted with respect. Physical and psychological safety are non‑negotiable.
Equal Access
Project roles, development paths and advancement follow clear, consistent criteria applied uniformly.
Fair Process
We document expectations and decisions to ensure transparency and comparability across cases.
Inclusive Collaboration
We integrate diverse perspectives into analysis and decision frameworks to improve outcomes.
Know. Love. Protect.
Sustainability
At Siller, sustainability is at the heart of everything we do. As a boutique advisory firm surrounded by the beauty of nature in Altenberg, we feel a special responsibility to protect our environment and act consciously in every decision we make.
Contribution to Marine Conservation
Siller GmbH is a continuous supporter of The Cousteau Society, encouraging all clients and partners to donate today to help protect our Water Planet.
Siller GmbH supports marine conservation through every purchase on siller.shop, with EUR 50 per item donated to The Cousteau Society and an option for clients to contribute the full production cost as well.
People
We believe in empowering our team and community through knowledge, awareness, and shared values. We promote environmental responsibility among our employees and partners, encouraging everyone to contribute to a more sustainable way of working and living.
Projects
Our team consists of experienced consultants with diverse backgrounds and areas of expertise. We are passionate about helping businesses succeed and are committed to delivering exceptional service to our clients.
Planet
Located directly beside a natural park, we feel deeply connected to the landscape that surrounds us. Our office operates entirely on solar power, and we use eco-friendly heating and air conditioning systems. Our business car is fully electric, and we prioritize train travel for business trips, taking advantage of Austria’s almost completely green electricity grid. Even our local community reflects our values: Altenberg’s decision to have no street lighting protects both people and wildlife, reducing light pollution and preserving the night sky.
Our Connection to Nature
Our office in Altenberg, surrounded by the serene beauty of the Wienerwald and close to the Altarm an der Donau, gives us a deep appreciation for the natural world. This unique location, right beside a protected landscape, reminds us every day of the importance of acting in harmony with nature.
The Wienerwald, often called Vienna’s green lung, is a vibrant mosaic of forests and meadows where around 70 percent of the trees are deciduous species such as beech and oak, joined by maple, linden, cherry, and wild service trees. Conifers like spruce, pine, and fir add to the forest’s resilience. This diversity ensures the forest can adapt and thrive, even in the face of climate change.
Just a short distance from us, the Altarm an der Donau (the old arm of the Danube) forms a calm and life-rich ecosystem that supports countless plant and animal species. The gentle flow of the river and the surrounding wetlands provide a vital habitat for birds, insects, and aquatic life, reminding us how balanced ecosystems sustain life at every level.
Living and working in such an environment is both a privilege and a responsibility. It influences our daily actions and strengthens our determination to operate sustainably. We take inspiration from the resilience and beauty of our surroundings and strive to contribute to their preservation through conscious business practices, renewable energy use, and environmentally responsible choices.
Responsibility
Our social responsibility is to raise decision quality beyond individual mandates. We contribute where our expertise creates measurable public value and avoid activities that compromise independence or introduce partisanship.
Public Interest
We support outcomes that strengthen institutional reasoning and consequence awareness.
Competence‑Based Contribution
We engage only where our domain knowledge has clear added value.
Non‑Partisan Stance
We do not align with political actors. Contributions remain evidence‑based and neutral.
Measured Impact
Commitments are specific, time‑bound and reviewed for outcomes rather than visibility.
Integrity
External engagement is governed by integrity and transparency. We work with clients, partners and suppliers who meet clear human‑rights and ethics expectations, and we disclose objectives and results at an appropriate level.
Client Suitability
We assess should we perform an engagement, not only can we. Ethical fit is required.
Partner Standards
Suppliers and collaborators must comply with explicit human‑rights, labour and anti‑exploitation norms.
Community Role
We participate in programs where our contribution improves capabilities and decision processes.
Transparency
External roles, goals and results are documented and proportionately reported.
Standards
Our standards of practice ensure method, consistency and traceability. They apply to every engagement irrespective of size or timeline and provide the operational foundation for decision‑grade advisory output.
Method
Assumptions, data sources and evaluation logic are defined upfront and followed systematically.
Traceability
Material judgments, model changes and sources are recorded and reviewable.
Process Reliability
Similar issues are assessed with the same criteria to enable comparability and auditability.
Quality Control
Senior review validates reasoning quality, data integrity and compliance with professional standards.
Who We Are
Siller is a business and management consulting firm based in Austria, serving Europe, the Middle East, and Asia. We are recognized for providing independent, objective valuations of companies and projects that give leaders the clarity and conviction to act decisively.
Siller — Established 2015 Austria
Company Name: Siller Handels GmbH
Address: Gemeindeweg 47, 3422 Altenberg, Austria
Company Register Number: FN 442495 d
VAT Number: ATU69992868
Siller is the consulting brand of Siller GmbH.
Siller GmbH is a limited liability company under Austrian law. The information provided on this website is for general informational purposes only and does not constitute professional advice. Siller GmbH accepts no liability for any actions taken based on this information.
© 2015–2026 Siller GmbH. All rights reserved.
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