Ordinary Differential Equations (ODEs) arise in many different aspects throughout mathematics and science (social and natural) one way or another and have a very wide range of applications in many fields. In recent years, many researchers have done a lot of studies in this field and made significant advances both in theory and in applications.

With the intention to provide an opportunity for the researchers in the area to report their most recent research findings, we proposed this special issue. It mainly focuses on periodic solutions and asymptotic analysis of ODEs, exploring the latest advances in the theory and in applications of ODEs. We have received numerous contributions, which cover very wide range of topics such as bifurcation theory and its application, stochastic systems, theory of limit cycles, and asymptotic analysis of systems with time delay. All papers submitted to this special issue had been sent to at least three external reviewers for peer review. Based on the reviewers' reports, we carefully selected some original works for publication.

In a single special issue, of course, there is no way to cover all recent advances in the area of Ordinary Differential Equations. But we do believe that the results published in this issue at least can reflect some of the most current trends in the area of Ordinary Differential Equations.

Acknowledgments

The guest editors of this special issue would like to take this opportunity to thank all our contributors for submitting their excellent work to this issue. Also, we extend our thanks to all the reviewers for being happy to be reviewers and their hard work. Finally, we extend our thanks to the editorial board members of this journal for their technical support and help during the whole period.

Maoan Han
Pei Yu
Valery Romanovski
Tonghua Zhang