Requirement engineering (RE) is the process of discovering stakeholders’ requirements and needs and documenting them in such a way that they can serve as the basis for all other system development activities. Despite recent advances in RE practices and tools, requirements engineers are still experiencing fundamental problems. Therefore, the identification and characterization of such challenges would help RE practitioners manage and overcome such difficulties allowing them to meet expected quality objectives. The main objective of this paper is to identify and compare RE challenges reported in the literature and in practice. To this aim, we have conducted a systematic mapping study to collect and analyze RE challenges in the literature. Furthermore, we have also conducted a questionnaire-based empirical investigation to collect and analyze RE challenges faced by IT practitioners working for 15 companies located in four different countries. Results show that the top challenges are the same in the literature and in practice. However, overall, our comparative study revealed a weak positive correlation between RE challenges in the literature and in practice (Spearman coefficient = 0.3061). This weak positive relationship indicates that some of the challenges found in the literature are not perceived by the participant to have a great impact on the practice. This may be due to the fact that solutions to (or guidelines to avoid) some of the identified challenges have been provided by the surveyed corporations.

需求工程（RE）是发现涉众的需求和需求并对其进行记录的过程，以便它们可以作为所有其他系统开发活动的基础。尽管最近在RE实践和工具方面取得了进步，但需求工程师仍遇到基本问题。因此，识别和表征此类挑战将有助于RE从业人员管理和克服此类困难，使他们能够达到预期的质量目标。本文的主要目的是识别和比较文献和实践中报道的可再生能源挑战。为此，我们进行了系统的制图研究，以收集和分析文献中的可再生能源挑战。此外，我们还进行了基于调查表的实证调查，以收集和分析为在四个不同国家/地区的15家公司工作的IT从业人员所面临的可再生能源挑战。结果表明，最大的挑战在文献和实践中都是相同的。但是，总的来说，我们的比较研究表明，文献中和实践中的RE挑战之间均存在弱的正相关性（Spearman系数= 0.3061）。这种弱的积极关系表明参与者没有意识到文献中发现的一些挑战对实践有很大的影响。这可能是由于以下事实：被调查的公司已提供了一些已确定挑战的解决方案（或避免指南）。