DARIAH (Digital Research Infrastructure for the Arts and Humanities) aims to support digitally-enabled research across the arts and humanities. The activities and service portfolios are centered around communities to enable transnational, interdisciplinary research (Kalman et al., 2014). Sustainable management of research data is one of the most important goals of DARIAH. To offer a common technological solution is challenging due to the heterogeneity of the tools and data. In this paper we analyse these problems, discuss a general concept for long-term storage in DARIAH, and present the current state of two implementations of the DARIAH Storage API (Funk et al.,2012). In the case of the DARIAH e-Infrastructure, widely-acknowledged standards and best practices are used to provide essential components for long-term storage. For implementing a long-term data management service, web services on a Representational State Transfer (REST) basis were selected as a solution, as they are lightweight and easy to understand. The DARIAH Storage API has a large support by most programming languages through frameworks and libraries. As DARIAH alr ... mehready provides some services for sustainable storage of data, the challenge of adapting the new DARIAH Interface is to provide a common base for different operation models. The first presented implementation of the DARIAH preservation interface, namely the Storage Service, is designed as stand-‐alone and easily adaptable for data centers. By using Java the Storage Service is platform independent and takes advantage of various standardized libraries. The data (resp. meta data) itself is currently stored in an underlying iRODS instance (resp. MySQL database). The design allows exchangeable components and backends to adapt to future developments. Every data center or small institution providing data can utilize it for a quick and easy link-up to the DARIAH infrastructure. The second implementation of the DARIAH preservation interface is done into an existing project, called Common Data Storage Architecture (CDSTAR) (Schmitt et al., 2013). It is designed as a data management middleware that links high-level web applications to low-level long-term storages interfaces in conjunction with NoSQL databases and search engines. The DARIAH preservation interface was added as a module with a small compatibility layer to the existing engine. It provides a link-up to the the DARIAH infrastructure as a Software-As-A-Service (SaaS) offering. Independent teams realized the adaptions and their test codes. For technical verification the test code was applied crosswise. This challenged the understandability of technical documentations. Additionally, DARIAH applications were run on both implementations in a Plug-Fest-manner. The increasing degree of networking in the arts and humanities requires a strategical preservation layer in the e-Infrastructure. The DARIAH Storage API is an approach to offer a common web-based interface to heterogeneous applications supporting digital humanities. Two independent implementations and sounded cross testing have proven the productive state to offer long-term preservation services to all interested application developers. Several services have already been relying on the presented preservation service as a sustainable storage backend.