KLC Law Firm is ranked in the Legal 500 2022 EMEA Guide

KLC Law Firm is ranked for a consecutive year in the Legal 500 2022 EMEA Guide. Legal 500 is one of  the most renowned legal directory in the world. The Legal 500 series contacts over 300,000 clients globally to obtain feedback on which law firms meet the criteria required by today's in-house counsel and business leaders, wherever in the world their work takes them.



Described by clients as ‘the go-to firm in Athens‘, KLC Law Firm has a strong reputation when it comes to domestic commercial and civil litigation; the team’s expertise also extends to high-profile arbitration, including both domestic and cross-border proceedings. In addition, the practice assists clients with pre-trial advice and associated risk assessment and out-of-court settlements. Recent highlights include its representation of Adidas Hellas in proceedings relating to the termination of a commercial agreement. The practice is jointly led by Aristides Chiotellis, managing partner and ‘impressive litigator‘ Panagiotis Tzioumas, Vassilis Voutsakis, Alexandros Tsirigos and Theodore Loukopoulos.


‘A full-service law firm with great response times, great expertise, in-depth knowledge of the client’s needs and reasonable billing practices. They always keep in touch.’

‘Panagiotis Tzioumas is a highly qualified legal professional and an exceptional people manager; he is client focused, always responsive and hands-on, and gives excellent strategic advice where required. Katerina Koutifari is a highly skilled professional and an experienced court lawyer, who is detail oriented, an expert in commercial and real estate disputes, and always supportive and responsive.’

‘KLC Law Firm has a dedicated and well-integrated team in the dispute resolution practice, who work very well together with other sector-specific practices of the firm.’

‘Their expertise, knowledge, efficacy and professionalism make them a standout in the Greek dispute resolution market. KLC Law Firm is more than a legal adviser to our company.’

‘Aristides Chiotellis has a particular ability to propose feasible solutions to the most complicated problems in various areas of law, on top of his unparalleled technical knowledge and expertise in civil and commercial law matters.’

‘Vassilis Voutsakis is a remarkably acute and experienced administrative law counsel and litigator and has extensive experience and knowledge of Greek administrative law and practices.’

‘The go-to firm in Athens. They are highly professional and very experienced.’

‘Panagiotis Tzioumas is one of the most impressive litigators I have come across in Greece. He works hard and is very dedicated, always knowledgeable about the file and quick on his feet.’



KLC Law Firm‘s ‘reputable‘ team is well versed in M&A transactions and restructurings, as well as advising on day-to-day corporate issues. At the forefront of its services are matters in the energy, hospitality and pharmaceuticals sectors. Founding partner Kostas Loukopoulos heads the team and has extensive experience in M&A, privatisations and takeovers. Other notable contacts include Peggy Zacharopoulou, who handles corporate transactions and litigation.


‘A reputable firm that is client orientated, with good communication and collaboration, robust knowledge of the legal sector and transparency in its dealings.’

‘Prompt communication and collaboration is what makes the difference between this law firm and their competitors.’ 

‘The strong points of KLC that are most worth mentioning are the ability to provide co-ordinated services on all the aspects of the transaction, and the unique combination of technical excellence and in-depth knowledge of the local market and competitive environment.’

‘The strength of the team is its realistic approach to the matters at hand combined with attention to detail.’

‘Theodore Loukopoulos exhibits great professionalism, dedication to the client’s goals and hard work. He strives to be pragmatic while protecting the client’s interests.’

‘Alexandros Tsirigos is knowledgeable and professional.’

‘We have worked with Alexandros Tsirigos and Xenofon Papayannis. What we have appreciated most is their ability to combine the delivery of the highest-quality services, in terms of technical excellence, promptness and efficiency, with an approach that is always attentive and client focused. It is also worth adding that they are also really nice people who know how to create a good and co-operative working climate.’

‘The team is composed of highly experienced, talented and entirely focused experts with distinct backgrounds who have local expertise and international business experience. The correspondence was immediate and precise, with constant feedback and adjustments.’



KLC Law Firm is trusted with an array of landmark assignments, assisting clients with significant energy projects and transactions. Recent work included acting as the legal adviser to First State Investment fund, which was shortlisted to the second stage of the international bidding process in relation to the electricity distribution grid operator DEDDIE. In addition, it is also advising Qatar Petroleum on the divestment of its stake in Heron II, operating a 420MW Greek gas fired power plant. Alexandros Tsirigos and Vassilis Karayiannis jointly lead the practice.


‘KLC is a strong legal team who are committed to the clients. KLC’s legal advice was practical and efficient, and helped us go forward faster.’

‘Alexandros Tsirigos has a talent in finding solutions for both parties and never proposes methods and tactics that makes things difficult.’

‘The team is an expert in the energy law. Always very helpful and attentive.’

‘They are solution oriented.’

‘This is a team that is highly responsive and takes a solution oriented approach towards complex legal issues. Their key advantage is their willingness to think outside of the box and adjust the processes to provide tailor made advice that meets business requirements.’

‘Very good knowledge of the Greek market – The team is responsive with quick answers – Very good drafting skills for highly structured transactions – Pro-activity.’

‘The energy sector constantly changes and is important to have a law firm that is updated and has deep knowledge. The team of KLC is highly capable to understand the challenges and consult effectively.’



At KLC Law Firm, a cornerstone of the work involves representing clients in proceedings before the Hellenic Competition Commission over allegedly anticompetitive conduct; in a recent highlight, it successfully acted for multinational construction company Vinci Construction Grands Projects in a landmark cartel case. In addition, the firm advises other clients on the competition aspects of concentrations, privatisations and private projects. Vassilis Karagiannis leads the practice.


‘We appreciate that in each project the team appointed consists of experts in the relevant legal field, as well as sector oriented professionals, something which is pretty unique in Greece.’

‘We would like to strongly recommend Dr. Vassilis Karagiannis. Dr. Karagiannis has a vast background and an extensive experience as competition law practitioner. He knows how to focus on the critical aspects of the cases he handles and has perfect command. He is extremely meticulous and methodological.’

‘Flexibility and very good knowledge of their business tasks.’

‘KLC Law Firm is an outstanding law firm in relation to EU and competition practice. The EU and Competition team has an outstanding experience in this practice and provides suitable and creative solutions.’

‘Dr. Vassilis Karagiannis is talented and a valued business partner. He is pragmatic and provides well considered advice to clients. He is the go-to lawyer for complex competition issues.’



KLC Law Firm acts for clients from a multitude of industries, such as healthcare, fashion, consumer goods, technology and media. Its expertise extends across the ‘whole spectrum‘ of IP matters, including copyrights, domain names, registration, industrial designs and trademarks. Recent work included assisting Firtech with IP matters involving both the licensing and supply of contracts in the USA and Greece. Theodore Loukopoulos heads up the practice.


‘Honest, clear, pragmatic with very reasonable charges.’

‘The team is responsive and eager to assist no matter how tight the deadline may be.’

‘The approach of the individuals is the same with the overall approach of the team. They are practical and client-oriented.’

‘Experienced with strong capabilities in pharma IP matters. KLC delivered favourable results in demanding and challenging IP litigation cases in Greece. KLC has an international flair that facilitates cooperation with out-of-country in house IP and vertical stakeholders.’

‘Partner Theodore Loukopoulos has demonstrated acumen and a hands-on attitude in a number of challenging patent litigation cases. Very competent in coordinating cooperation between in-house attorneys, experts and external counsel in complex IP disputes.’



KLC Law Firm has a growing transactional practice, handling mandates for international and local financial institutions, corporate borrowers and rating agencies. In addition, the team draws on the firm's disputes, energy, hospitality and other departments to offer further services to clients. 'Excellent' managing partner Panagiotis Tzioumas leads the team, and is noted for his extensive experience in project finance, debt restructuring, NPL transactions and the implementation of EU financial instruments.


‘Vey knowledgeable and competent professionals with a practical approach to resolving commercial and legal issues.’

‘An efficient and hardworking team of transactional lawyers, providing proper and accurate legal advice and well-articulated deliverables.’

‘Panagiotis Tzioumas has an understanding of complicated global legal issues and is in a position to identify the material aspects of a matter and recommend the best available course of action. Panagiotis Krystallis is always responsive and diligent. Arianna Chatzimarkou is a young and dynamic member of the team.’

‘Well prepared and come up with innovative proposals during negotiations with financial institutions. Very good approach to counterparties’ legal advisers and ready to lead negotiations while also being very capable of dealing with delicate issues.’

‘Arianna Chatzimarkou is very professional and calm and always very well prepared. She knows her stuff and plays a great role in supporting Panagiotis Tzioumas during negotiations. She has excellent drafting skills.’

‘Panagiotis Tzioumas makes himself available at short notice in urgent cases. He is an excellent lawyer, combining high-quality legal skills, business acumen and negotiating skills, and ensures the quality of his team’s deliverables.’

‘Arianna Chatzimarkou is an excellent young lawyer, providing accurate and reliable legal advice.’

‘What is useful for us, as clients, is that the firm works through small teams of two or three lawyers, which results in all team members being up to date with developments on the case, irrespective of their core competencies. This also caters for immediacy in response and a proper flow of feedback between the firm and the client.’



KLC Law Firm is a 'pioneer in the provision of legal services in the privatisation sector', according to one of its clients. It acts for First State Investments, Attiko metro and Hellenic Republic Asset Development Fund, among others. Xenofon Papayiannis, Vassilis Papayiannis and Alexandros Tsirigos jointly lead the practice, combining their experience as legal counsellors before the Independent Power Transmission Operator, Hellenic Gaming Commission and PPC Renewables.



KLC Law Firm is highly active in a broad cross-section of real estate investment transactions and construction projects. Theodora Xythali and Ioanna Lazaridou jointly lead the team, which is experienced in matters involving wind parks, logistics centres, commercial and industrial premises, offices, residential buildings and tourist settlements, among various others. It is increasingly active in the hospitality sector, where the work includes developments of luxury hotel complexes. In addition to undertaking non-contentious work, the firm also acts for clients in disputes.


‘This is a team that can be adaptive to customer needs whilst keeping the high level of services.’

‘Kosta Kotoulas has a solid foundation of real estate with an eye to detail and the skill to present the information in a business friendly way. Typical of the law firm, he is also willing to consider innovative approaches to address complex issues.’

‘Nice team, dedicated and professional.’



KLC Law Firm handles tax matters for clients from a range of industries, including manufacturing, pharmaceuticals, agriculture and construction. Notable work included its representation of Adidas before the Greek Administrative Courts and the Supreme Court in relation to custom penalties due arising from inaccurate customs declarations. Xenofon Papayiannis leads the practice.


‘Set quality standards for the expected outcome of their work. Focuses on the achievement of results acting with integrity and a strong sense of responsibility.’

‘The team I worked with showed full availability and provided answers promptly as requested.’

‘The straightforward approach to solve the issue at stake was very appreciated. The people I worked with were very kind.’

‘Highly responsive, available and engaged. Exceptional quality of work.’

‘They are dedicated to the goal and demonstrate attention to detail.’

‘Dora Kantartzi; responsive and gave clear and pragmatic advice in a very niche area.’

‘KLC has an experienced and qualified team of tax experts. They have profound knowledge in their field and they inspire trust.’

‘The members of KLC law Firm’s Tax team are always available, well-informed, organized, easy to talk to, sincere and very qualified. I have collaborated with Mr. Xenofon Papayiannis and Mrs Dora Kantartzi. They are both exceptional. We have collaborated for tax advice and tax litigation and I was very satisfied with the services received.’

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