**1. Introduction**

Many disruptive innovations require complementary innovations to attract customers and succeed [1]. As a result, innovative firms have become increasingly dependent on the efforts of other innovative actors within their environments [2]. Managing such dependency and complementary innovations outside firms poses significant challenges for many organizations [3], especially in emerging economies, where the number of innovative firms remains low [4].

Several models, such as supplier innovation, strategic R&D [5, 6], and the innovation ecosystem (IE), have been proposed to explain how innovative firms work with other creative partners. Among them, IE literature moves beyond the challenges

within firms by encompassing the development of complementary products and services in addition to the main ones. Furthermore, it explores the interdependencies and coordination between partner organizations that jointly create value [2]. IEs comprise focal firms, suppliers, complementary innovators, customers, and other actors [7]. However, recent studies have raised several questions about how actors' interactions impact the emergence and evolution of IEs [8–11]. These questions indicate that the IE concept has not yet been consolidated [7], especially in emerging economies [12], where firms face an environment of resource scarcity, structural gaps, and institutional voids [13].

To strengthen empirical research and manage the theoretical flaws of ecosystems, scholars have recommended applying a hybrid view of biological systems and industrial engineering systems [14]. A similar approach has also been proposed to study supply chain management by merging the literature on business operation and System of Systems (SoS) engineering [15]. SoS can provide a complementary perspective based on actors' interactions. SoS is an assemblage of individual systems with operational and managerial independence that work together as collaborative systems [16]. SoS focuses on integrating multiple complex systems supported by different managers, sponsors, funding, and goals [17].

Accordingly, by combining IE and SoS literature and exploring multiple cases of armored vehicles within the Brazilian defense industry, this study aims to elaborate on the following research question: considering the typical organizational environment of emerging economies, how do actors and their interactions impact the emergence and evolution of IEs?

This chapter is organized into six sections. The following section outlines the literature on IE, presents the types of authority in SoS, and introduces a tentative framework for analyzing ecosystems. The research method, case selection, and data collection are then described. Later, the cases are presented in detail and followed by a discussion that scrutinizes the impact of the organizational environment, the actors' roles, and their interactions in IEs. The last section summarizes the study's main contributions and limitations and offers suggestions for further research.
