Our team and expertise

As a dynamic and joyful team, we flexibly combine our skills to develop goal-oriented solutions. Our team brings together people with different backgrounds and capabilities. We collectively speak 18 languages and have spent 90 years living abroad. Our team members move joyn-coop forward in an entrepreneurial spirit.

The entire team is trained in agile project management and regularly participates in customised training sessions, carried out by external and internal specialists, to foster their personal and professional development.

Christina Kükenshöner

Managing Partner

Christina Kükenshöner is co-founder and managing partner of joyn-coop where she focuses on driving sustainable development with agile approaches.

Christina is very passionate about the Sustainable Development Goals and has made it her mission to assist companies, development finance institutions and foundations to pursue the SDGs in their activities. She has been involved in over 90 projects and has extensive expertise in helping clients with structuring funds and programmes, especially in fragile and complex settings.

Christina is an experienced process facilitator and has trained as an agile coach to assist clients in making their organisations more flexible in adapting to complexities and a rapidly changing environment.

Prior to founding joyn-coop, Christina served as a management consultant at McKinsey & Company and as a senior project manager for Financial Cooperation at KfW Development Bank. She holds a master’s degree from the Harvard Kennedy School.

Christina is a mother of three and enjoys playing the trombone and the piano.

Dr. Christiane Ströh de Martínez

Managing Partner

Dr. Christiane Ströh de Martínez is co-founder and managing partner of joyn-coop. She is passionate about truly participatory approaches and creating spaces for deep listening and energetic co-creation within joyn-coop and in other organisations.

Throughout her 15 years in development cooperation, Christiane has evaluated, designed and accompanied development projects across Africa, Asia, Europe, and Latin America. She brings her expertise in participatory methods, co-creation and strategy development to leading change processes, both as a moderator and process facilitator. Her sectoral focus is on inclusive finance, local economic development, inclusive agri-business and sustainable small-scale farming.

Before founding joyn-coop in 2011, Christiane worked as a free-lance consultant in development cooperation and served as a visiting professor at several German universities, teaching a wide range of development-related subjects. In her PhD thesis in economics, she conducted research on inclusive financial sector development and microfinance. She further holds a Diplom degree (master-level equivalent) in International Economics and Latin American studies. Christiane is fluent in German, English, French, Spanish and Portuguese.

Christiane loves to spend time in nature with her family and friends – and bring home fresh leaves for her guinea pigs from her outings.

Corinna Strohbach


Corinna Strohbach is a consultant at joyn-coop. She is passionate about financial sector development and combatting climate change.

Her work includes project development as well as conducting conceptual studies and evaluations for key actors in German development cooperation. Corinna is experienced in data analysis and is adept at breaking down complex facts into clear visualizations. Moreover, she enjoys moderating workshops and facilitating processes in diverse cultural settings. Her sectoral focus is on financial sector development, employment promotion and food security/nutrition. Since 2018, Corinna is also a certified trainer for microfinance action learning games.

Before joining joyn-coop, Corinna worked with a regional GIZ project in Asia, supporting the introduction of inclusive insurance. She holds a master’s degree in International Development Studies from Philipps University Marburg and bachelor’s degrees in Economics and Human Geography from Goethe University Frankfurt.

Corinna is enthusiastic about sustainable living and travelling by trains. She enjoys all kinds of racket sports.

Christoph Renken

Senior Consultant

Christoph Renken is a senior consultant at joyn-coop with six years of experience in development consultancy.

Christoph’s work is focused on development cooperation in fragile and conflict-affected contexts, as well as refugee and mixed migration settings. He has extensive experience with approaches and procedures of German Financial Cooperation and, inter alia, worked as an implementation consultant for a KfW project in Uganda. Christoph regularly conducts conceptual studies, feasibility studies, peace and conflict assessments, and project evaluations. His passion for innovative approaches has led him to develop a methodology for rapidly selecting and appraising NGO projects, prepare strategic studies on engagement in fragile states, and conduct remote evaluations for inaccessible project areas with the help of online tools and local consultants. Christoph has also designed several funding mechanisms for regional organisations.

Before joining joyn-coop, Christoph worked in a GIZ sector project that advised the German government on transitional development approaches. He holds a magister degree (equivalent to master’s) in political science, law and comparative religious studies from the University of Munich.

Caroline Gruber


Caroline Gruber is a consultant at joyn-coop with a focus on francophone Africa. She is passionate about seeing people grow and developing approaches that strengthen their skills.

Caroline’s areas of expertise comprise vocational training, health, livelihoods and rural development, facilitation of Financial Cooperation with NGOs and regional organisations as well as private-public cooperation. In these areas, she conducts feasibility studies, conceptual studies and evaluations. As an integral part of her work, Caroline facilitates workshops and uses participatory methods to enable stakeholders to contribute their insights and perspectives. While her regional focus is on West and North Africa, she has also gained experience in East Africa and Southeast Asia.

Prior to her work at joyn-coop, Caroline worked with GIZ supporting rural livelihoods in central Vietnam. Caroline holds a Master Degree in International Relations from the Political Science Institute of Aix-en-Provence (France) as well as a Master Degree in political science from the University of Freiburg (Germany). She is a German and French native speaker.

Caroline comes from a family of gastronomes and loves to discover new culinary highlights in countries she travels to.

Jannis Hussain

Junior Consultant

Jannis Hussain is a junior consultant at joyn-coop with a particular focus on issues related to political economy and climate change. He started working at joyn-coop in 2018 and has since contributed to research and analysis on a wide range of issues including state fragility, migration, and infrastructure planning. Jannis is especially interested in structural challenges at the intersection of development and the environment and the use of experimental and causal inference methodology in evaluations.
Prior to joining joyn-coop, Jannis completed internships and work placements at the Permanent Mission of Germany to the United Nations in New York, Allianz SE, and Kiron Open Higher Education, a social start-up enabling refugees to gain a tertiary education. He recently completed his MPhil in International Relations at Oxford University and holds undergraduate degrees in Politics and Economics (B.A.) and Psychology (B.Sc.) from the University of Munich.

Jannis loves environmentally friendly forms of travel and is currently scouting out his next hitchhiking destination.

Ricarda Bollmann

Head of Operations

Ricarda Bollmann is the Head of Operations of joyn-coop. As experienced financial controlling and reporting practitioner, she oversees the finances and internal processes of joyn-coop.

Over the course of her 15-year career, she has lived, studied and worked in Germany, Japan, Hong Kong, South Korea, Singapore and Saudi Arabia. Her work for a variety of companies across the semiconductor and financial services industries has equipped her with extensive knowledge about various accounting and reporting requirements. Ricarda holds an MBA from Heriot-Watts University and an MSc in Area Studies (East Asia) from the University of Duisburg.

Ricarda enjoys her daily walks with her dogs.

Núria Garcia-Dotor Girbau


I am Núria, currently an intern at joyn-coop. Being a Master student in International Development at Sciences Po Paris, I am thrilled to join this team to be part of actual projects creating solutions for development challenges. As a start, I will be working on the design of a funding facility which seeks to improve the living conditions for the population in the Sahel region. Indeed, concepts as “security-humanitarian-development nexus”, “participatory methods” or “strengthened social cohesion and governance” are a constant in my Master studies, and I couldn’t be happier to apply them within my internship!

I have also interned for IIEP UNESCO and Red Cross and volunteered in international projects every summer since I am 16 years old. I like to be locally involved; to absorb from other cultures and diversity; and I can’t decide whether I love more a trip to the seaside or to the mountain landscape.

Lina Ghosh


Lina Ghosh is a consultant at joyn-coop whose work focuses on organizational and programme development, in particular in contexts of migration, displacement and state fragility.

She has extensive expertise in process facilitation, where she employs agile and participatory methods and adapts them to participants’ organizational ranks, ranging from field workers to top managers. Lina has worked with a variety of organizations, including NGOs and think tanks. She has advised KfW Development Bank, the EU and various UN organizations.

Prior to her work with joyn-coop, Lina supported large private companies in the industrial and insurance sector as a consultant with McKinsey & Co. Thanks to her multicultural background and international study and work experience, she is fluent in German, English, French, Russian and Bengali and has in-depth knowledge of the post-Soviet region and South Asia. Lina holds a master’s degree in International Development and a bachelor’s degree in Social Science from Sciences Po Paris.

Lina has a passion for learning new languages and travelling to unusual destinations.

Clemens Rossmanith

Junior Consultant

Clemens Rossmanith is a junior consultant at joyn-coop. He is passionate about innovative solutions to poverty reduction and environmental sustainability.

As a consultant at joyn-coop, Clemens focuses on the development of strategies to ensure project success in fragile and conflict-affected states. He further works on promoting sustainability in infrastructure investments.

Before joining joyn-coop, Clemens gathered extensive working and research experience in Nepal. He has also worked in a GIZ project in India, contributing to the drafting and implementation of policies for climate change adaptation in several states of North-East India. He holds a master’s degree in “Global Change – Regional Sustainability” from Leopold-Franzens University Innsbruck, where he focused on development studies and rural development, and a bachelor’s degree in Geography from Ludwig-Maximilians University of Munich.

Being an outdoor enthusiast, Clemens loves to be active in the mountains.

Rosa Eckle

Senior Consultant

Rosa Eckle is a senior consultant at joyn-coop with more than 13 years of experience in development cooperation. She is passionate about supporting new partnerships and development organisations with a change agenda – always with the aim of increasing impact on the ground. Her thematic focus is the provision of basic social services with a focus on education, skills training and sexual and reproductive health and rights. Most recently, Rosa accompanied a one-year partnership process between KfW and UN organisations which aimed to streamline processes for more efficiency and impact in joint projects.

Before joining joyn-coop, Rosa was a project manager at KfW Development Bank, where she acquired first-hand experience of German Financial Cooperation’s sectoral approaches, working principles and procedures. Rosa holds an MPhil Degree in Development Studies from Oxford University and a bachelor’s degree in Economics and History from SOAS University. She completed her studies with a postgraduate training at the German Development Institute in Bonn.

Rosa enjoys sports, particularly African dancing, and interacting with different cultures.

Bettina Bauer

Senior Consultant

Bettina Bauer is a senior consultant at joyn-coop. Her enthusiasm for municipal development and conflict prevention has brought her in touch with a range of multisectoral issues and approaches to development cooperation.

Bettina consults on subnational governance and municipal service provision, as well as international cooperation projects in fragile contexts and areas affected by displacement. She further specializes in violence prevention in urban agglomerations, and municipal development adapted to climate change. Her 15 years of experience in development cooperation in numerous African and Asian countries and profound knowledge of a variety of approaches and related procedures make her a valuable partner for finding solutions to challenges related to project management. Beyond studies, thematic assessments and evaluations, Bettina has been the author of numerous hands-on guidelines and issue papers for German Financial Cooperation.

Before joining joyn-coop, Bettina worked as a freelance consultant and served as a visiting lecturer, teaching on the structural characteristics of developing countries and emerging economies. She has also served as a project manager at KfW Entwicklungsbank and holds a master-level degree in Public Policy and Management from the University of Potsdam. Bettina completed her studies with a postgraduate training programme at the German Development Institute. She is fluent in German, French and English.

Bettina is a mother of three, a passionate choir singer, and loves to please others with her homemade cakes.

Marie Samba


I am Marie, I joined joyn-coop as an intern in mid-August. As a student in a dual BA between Sciences Po and Columbia University I am studying political science and ethnic and racial issues. I deeply care about health access and cultural diversity. Ever since my internship at Doctors Without Borders in 2016, I have wanted to understand from inside the design of international development projects. By supporting the team with an evaluation mission on a reproductive health and rights program, I have and will continue to learn how develppment projects are built and assessed. Even with the constraint of working remotely from France, I could not have dreamed of a better opportunity to work on such interesting topics, in such a stimulating and constructive environment.

I like to balance my days between working intellectually for remote projects and meeting and helping more “tangible” people. That’s why, in my spare time, I am involved in an association working for the integration of refugees in my area. I also love handball, the Atlantic Ocean and hiking!

Theresa Höllerer


My name is Theresa Höllerer, I´m 22 years old and from Munich. After finishing my bachelor’s in business administration with focus on International Management, I was looking for a field of work that is both demanding and generating added value. That´s when I came across joyn-coop. The company impresses me by clearly standing out from conventional consultancies due to its international orientation, focus on development topics and interdisciplinary. In my first few days I have already been able to work on two exciting projects: One in Niger, dealing with the educational and health situation of young girls. The other one in the Philippines, engaged with building microfinance structures in rural areas. It makes me proud to be both working on something meaningful and together with such an open-minded and inspiring team, having contacts and acquaintances across the globe. National barriers disappear with just a zoom call- that’s lived globalization!

Working in an international context is very important to me. I have always been fascinated by foreign countries and global contexts. Accordingly, I have aligned my studies as internationally as possible, learning in Scotland, Colombia and Lithuania. During my internship in the Committee on Humanitarian Aid and Human Rights of the German Bundestag, my year-long in several organisations, I developed a strong interest in global sustainability and justice. That´s where I see my professional future!

In my free time I love everything that can be done outside: hiking, biking, photography….