The Hippo pathway is an evolutionarily conserved regulator of tissue growth. At the core of the Hippo pathway, a kinase cascade represses the activity of a transcriptional effector, an oncoprotein called Yorkie. Multiple upstream inputs synergistically promote the activity of the kinase cascade from the apical cortex of polarized epithelial cells. How these upstream components organized and regulated at the cell cortex is poorly understood. One of the key upstream components, Kibra, localizes at the junctional and apicomedial cortex. In the absence of a conventional receptor/ligand pair, it remains unknown what controls the organization of Kibra, how its activity is regulated, and whether Kib-mediated signaling is modulated by any stimuli.In this dissertation, I investigate the upstream Hippo signaling, focusing on the regulation and organization of Kibra. I will first demonstrate that ubiquitin-mediated degradation is a major mechanism that regulates Kibra-mediated Hippo pathway activation. Specifically, when Kibra assembles a signaling complex, it is ubiquitinated via the SCFSlimb E3 ubiquitin ligase machinery and subsequently degraded. Next, I will show that actomyosin generated tension promotes Kibra degradation. Mechanistically, tension promotes cortical association of the Ser/Thr kinase Par-1, and Par-1 promotes Kibra degradation. Finally, I examine the subcellular association of Kibra with the actomyosin network. I find that Kibra organization at the cell cortex is modulated by actomyosin dynamics, whereby apicomedial actomyosin flows promote medial Kibra accumulation and Hippo signaling activity. Additionally, I provide evidence that Kibra is tethered via the apical polarity network at the junctional cortex. Collectively, these findings expand our understanding of upstream Hippo signaling organization and regulation and how actomyosin dynamics can modulate these processes.