The current second quantum revolution heralds the biggest technological advancements of the twenty-first century. At the forefront of this is the development of quantum computers, which promise to bring transformations to almost all sectors, from banking to drug research. With rising investments in developing full-scale, fault-tolerant quantum computers, the quantum computing provider market is starting to saturate with incumbents. In order to succeed, firms operating in this market need to start acting competitively. However, despite vast research on the potential applications, technological development and responsible innovation, little is known about strategic factors that drive the market.

To address this issue, this work identifies, describes and contextualises the use of alliances in firms’ business strategy in the quantum computing business ecosystem. Through literature review, publications of various types of collaborations on firms's websites, and interviews with four experts in the industry, the work describes the quantum computing business ecosystem, links the cooperations to literature on strategies, and provides contextual implementations of various alliances.

First, a value proposition is constructed, containing five components: Hardware providers, cloud service providers, quantum software providers, managed services providers and end-users, each with its own set of challenges and strategies attached to it. Furthermore, two technology strategies pursued by firms can be identified: an open innovation approach and a full-stack approach. The use of various types of collaborations are described, including licensing, standards agreements, business networks, joint marketing, selling and offering agreements, consortia, strategic partnerships, mergers and acquisitions, and joint ventures.

For SMEs, alliances through bidding consortia, formed for tenders and subsidies, are the main use of cooperation. Strategies herein are the acquisition of capital, reduction of R\&D costs, early product show-off, and staying in the loop for technological decision making on standards. Other partnerships are aimed at figuring out relationships with other firms in the industry, and fostering standardisation through the release of open-source software. The former is characteristic of the nascent ecosystem's formation, as the value proposition is still unclear and the industry's architecture is not set. The use of open-source software has also played a key role in the development of the classical computer, and firms are seen to adhere to a similar approach. Furthermore, we contextualise the strategic differences between the full-stack and open innovation approaches that are seen within the ecosystem. Where firms in the former are challenged by technical inflexibility, low sales volume and vast investment costs, firms in the latter need to balance an appropriability-adoption dilemma, create sufficient alignment with their value proposition and use extensive cooperation to ensure compatibility and modularity. However, through this, they get to enjoy increased economies of scale and agility.

All in all, the strategies can be summarised in two main categories: procurement of resources and embedding into the ecosystem. The work in this thesis encompasses a multitude of related fields including competitive strategy, ecosystems and alliances, and discusses the quantum computing industry from the standpoint of the technology providers and developers, which should aid managers in evaluating their strategic position in the ecosystem and in drafting cooperation strategies. From an academic perspective, this work provides the first managerial study of the quantum computing market from the standpoint of the technology providers. In addition to strategies, it identifies a lack of alignment of end-users as a key inhibitor to the constitution of the value proposition. Moreover, the findings of this thesis support the hypothesis that pre-adaptation-phase strategies are aimed at constituting Ortt and Kamp's technological innovation system (TIS) framework's building blocks, an important step to understanding ecosystem formation dynamics.

Lastly, we identify several key areas for future studies. This includes validating and strengthening the conclusions of this work through additional expert interviews, which should also help in exposing nuances in strategy between firm sizes, position in the value chain and geolocation, as well as similarities and differences with the development of the classical computer. Furthermore, future studies are suggested to investigate the differences in efficiency and effectiveness of governmental funding in the quantum industry, characterise end-users based on their expected moment of engagement with the quantum computing market, the role of alliances in quantum computing platform formation, and the link between innovation-phase strategies and the TIS framework's building blocks.