This research aims to advance strategic management for the 21st century by investigating cross-sector partnerships to solve complex societal problems. As part of the People, Cities & Nature research program funded by the Ministry of Business, Innovation & Employment (MBIE UOWX1601), this study analyses how CSPs are impacting urban ecological outcomes. The overarching research question is: How do CSPs achieve positive impacts for urban ecology? The sub-questions are broken into two categories: strategy and urban ecology impacts. To uncover the latest insights into CSP strategies and the impacts achieved by CSPs, the subquestions are: How can different sectors collaborate effectively?; What are the frequently identified barriers to effective collaboration?; How is success measured within CSPs?; What impacts are being achieved for urban ecology?; and What is different or unique to urban ecology partnerships? A qualitative cross-case analysis was used, based on six case studies in New Zealand across local, regional, and national scales. Several partners from each case study were interviewed across a range of sectors- public, private and community. Also interviewed were experts in CSPs not directly involved in the cases, but with experience across multiple partnerships. A total of 30 people were interviewed using a semi-structured approach, and each interview was transcribed and uploaded to NVivo. NVivo was used to disassemble the data for a thematic analysis on how to be effective, measure success, and what impacts were achieved. Then a four-stage thematic analysis was carried out to uncover insights. Systems thinking was applied to bring together strategic management and urban ecology concepts as a framework for understanding CSPs for urban ecology. Systems thinking allows the researcher to model and compare CSPs of varying complexity, scale, and temporal elements as part of one system. Using a systems thinking approach, impacts related to all the pillars of sustainability- ecological, economic and social- are examined. By applying systems thinking, diverse people across a system can scale up impact by combining their resources and levers to harness public interest and tackle major societal issues. However, it takes a high degree of collaboration to maximize efficiency and impact. This research explicates how managers can capitalize from collaboration and benefit the organization and wider society. The researcher initially aimed to identify successful CSP models that engaged in the private sector; however, the data showed that people and relationships play a much greater role in longevity, success and impact. When comparing the four skillsets for effective collaboration, the data showed interpersonal skills were the most valuable to build and maintain relationships. It is well known that trust is a critical factor in effective CSPs as it is the foundation for a strong relationship. The data showed that relationships enable a network to form in pursuit of a common goal or shared values. Growing and strengthening the network is the key to creating system change that mutually benefits the planet, people and profit. The main barriers identified were time and monitoring and evaluation data. What this research uncovered is that personalities play a significant role in CSP success. Because CSPs scale up impact as they grow, the right personalities could attract large groups of people to the network, therefore amplifying positive impacts. This type of persona is called a “connector”, a new term for CSP theory. Ultimately, this research aims to make CSPs more accessible to all sectors. Given the private sector’s impact on ecological and social issues, businesses have immense potential to contribute to the 2030 SDG targets. The CSP activity happening in 2020 to address the grand challenge of biodiversity loss will be captured by this study. Using the partnership monitoring and evaluation framework, this study classifies the CSP impact on urban ecological outcomes and benefits to wider society. By fusing strategic management and urban ecology theory, a new framework is proposed for people to conceptualise their own cross-sector collaboration and impact: Connect, Align, Grow and Evolve.