"in-depth partnership" is a correct and usable phrase in written English.
You can use it to describe a working relationship between two or more parties in which they share resources, knowledge, and expertise in order to solve complex problems or to pursue common goals. For example, "The nonprofit organization sought out an in-depth partnership with the larger corporation in order to receive additional support for their social programs."
Meanwhile, Mapify currently generates revenue through in-depth partnerships with travel companies such as Airbnb.
It supports community responses to HIV/AIDS through community capacity strengthening and in-depth partnerships in order for communities to reduce HIV/AIDS incidences, improve access and adherence to treatment, provide adequate care and support, and mitigate the impact of the epidemic.
Although many universities have outreach programs that support volunteer scientists entering K 12 classrooms, in-depth partnerships between teachers and scientists must be developed and nurtured to adequately prepare these scientists to contribute substantively to STEM learning (Tanner et al., 2003).
As the extensive lab coats illustrate, though, Married At First Sight is an in-depth study of partnership.
"Unfortunately, the assassination of Mr. Rabbani has thrown the whole exercise into a serious difficulty; it almost ended the negotiations between us," Mr. Karzai said in a news conference, adding that he hoped the investigation would "lead us to more fruitful and in-depth continuation of partnership between Afghanistan and Pakistan".
Josh Constine has a more in-depth analysis on the partnership here and here.
Some elements of the Pfizer-IAVI partnership's success reflect factors identified in the literature on capacity building; for example, IAVI's readiness for capacity building, the long-term nature of the partnership which allowed in-depth understanding of needs and time to develop capacity, and the adaptation of capacity building strategies to the specific needs of vaccine research.
The partnership will deliver in-depth certified vocational training, financial and enterprise skills training to young people in 8 districts of Punjab, ensuring they have the knowledge and confidence to become agents of change with enormous potential for transforming societies and as a key resource for prosperity in their communities.
To explore these complexities in depth requires partnership with terminally ill children and adolescents, and acknowledgement of their active social and moral agency in research.
Apple has deals with Facebook and Flickr for iPhoto, but no word yet on any partnerships for the in-depth integration that Twitter has with iOS 5. Apple's choice of Twitter for this in-depth integration fits in nicely with Twitter's recent rollout of its own-photo sharing service.
