The empirical fields of research by Hans-Jürgen Lange on the one hand lie in the field of political system analysis and on the other hand in the field of security research. In the field of political system analysis, he examined modernisation processes in parliaments, political parties and associations and in the same way organisational reforms and policies in parliamentary parties as well as state and administrative reforms, particularly in connection with the introduction of New Public Management approaches and procedures and their control- and democracy-theoretical problems.

A cross-cutting issue in this regard was constituted by questions related to impact research and social compatibility when using information and communication technologies in political organisations and institutions.

In the field of security research, Hans-Jürgen Lange was responsible for the conceptual development of the approach of a policy analysis on internal security. It examines the interrelation between actors, structures, processes and political contents when making political decisions. The corresponding studies first focused on police forces, including historical and sociological aspects. The developments of phases in the definition of problems, the agenda shaping and implementation of political programmes of police and criminal politics as well as the internal security politics on the whole are at the centre of interest here. His research work was extended to include further actors of the security system – so for example to the fields of disaster protection, which was the subject of an extensive research project and the fire brigades.

In a further research project, Hans-Jürgen Lange, together with a legal project partner, examined the formal and above all informal influences on legislation processes in the field of internal security policy.

The comprehensive objective is to analyse how the change of the security system, as can be observed in all Western societies, will affect theory and practice of statehood, administration and democracy and to point out the consequences in particular for the constitutional and democratic condition of social order.

Professor Lange’s research work is determined by three theoretical approaches: At the organisational analysis level, this is the theoretical approach of micro politics: how do individual actors act within the structural framework of an organisation, what are their strategies, which objectives do they have, which arrangements do they make with other actors, which effects do these actions have on the structures of the organisations themselves? At meso level, things are more complicated. Here organisations fight for power, influence and are driven by the idea of enforcing their ideas in the political arenas.

This is where the policy analysis starts. On the one hand, it examines actors, structures, decision-making processes and the political programmes which determine the political area. On the other hand, it raises the question as to who will prevail in this field with what kind of action-directing orientations? A number of theoretical approaches, for example the coalition-theoretical approach, provides appropriate instruments to reconstruct these negotiations. Things will be most difficult at macro level. Approaching the subject from an action-theoretical point of view and thus explaining macro phenomena on the one hand and on the other hand drawing conclusions from the consequences as well as repercussions of the structures of state and society for the actions of the individual actors meets with big theoretical and methodical problems.

All this is based on the approach of an action-oriented institutional theory, trying to show the correlations between action and system. In this perspective, strongly influenced by Max Weber, above all historically influenced developments are of interest, the differentiation of normative action and order models, the diffusion of meaningful concepts of knowledge and ideas, the negotiation of institutional arrangements and rules – hence the institutionalisation and change of social order.

The development of training and higher education systems has turned out to be Hans-Jürgen Lange’s all-embracing topic for work. Here on the one hand the question is how knowledge (e.g. the scientific findings of security research) can be processed, shared with and communicated to others so that it can be employed and used as action-relevant practical knowledge. This makes high demands for example on the conception of fundamental study programmes and even more on advanced training concepts. At the same time it must be ensured that any application orientation of knowledge in teaching will not negate basic orientation in research and thus by definition annul the possibility of “unpredictable” knowledge.

On the other hand, this leads to the question as to what future education and training organisations in general and universities in particular should look like in order to maintain the balance between a rapidly growing wealth of theoretical knowledge becoming obsolete at ever shorter intervals and the production of knowledge confronted with increasingly stringent useability requirements. From this point of view, knowledge cannot be separated from education and training. Education and training, according to the hopeful assumption of the scientist and university lecturer, provides the framework for generating reflexive knowledge and thus for promoting the individual (in the best case also social) ability to take the courage and responsibility for “differentiated difference” whenever and wherever this is necessary in private and even more so in social and political situations.

• Zukunft der Polizei. Trends und Strategien. Hrsg. (H.-J. Lange, Th. Model und M. Wendekamm), Wiesbaden 2019, 286 S.
• Die Verwaltung der Sicherheit. Theorie und Praxis der Öffentlichen Sicherheitsverwaltung. Hrsg. (H.-J. Lange und M. Wendekamm), Wiesbaden 2018, 281 S.
• Verfassungsschutz. Reformperspektiven zwischen administrativer Effektivität und demokratischer Transparenz, Hrsg. (H.-J. Lange und J. Lanfer), Wiesbaden 2016, 199 S.
• Kooperation im Katastrophen- und Bevölkerungsschutz, Hrsg. (H.-J. Lange und Ch. Gusy), Wiesbaden 2015, 313 S.
• Cyber-Sicherheit, Hrsg. (H.-J. Lange und A. Bötticher), Wiesbaden 2015, 293 S.
• Dimensionen der Sicherheitskultur, Hrsg. (H.-J. Lange, M. Wendekamm und Ch. Endreß), Wiesbaden 2014, 396 S.
• Versicherheitlichung des Bevölkerungsschutzes, Hrsg. (H.-J. Lange, Ch. Endreß und M. Wendekamm), Wiesbaden 2013, 271 S.
• Innere Sicherheit im europäischen Vergleich. Sicherheitsdenken, Sicherheitskonzepte und Sicherheitsarchitektur im Wandel, Hrsg. (Th. Würtenberger, Ch. Gusy, H.-J. Lange), Berlin 2012, 346 S.
• Auf der Suche nach neuer Sicherheit. Fakten, Theorien und Folgen, Hrsg. (H.-J. Lange, H. Peter Ohly und J. Reichertz), Wiesbaden 2008, 2. Aufl. 2009, 407 S.
• Kriminalpolitik, Hrsg., Wiesbaden 2008, 469 S.
• Wörterbuch zur Inneren Sicherheit, Hrsg., Wiesbaden 2006, 407 S.
• Polizei im kooperativen Staat. Verwaltungsreform und Neue Steuerung in der Sicherheitsverwaltung (zus. mit J. C. Schenck), Wiesbaden 2004, 462 S.
• Die Polizei der Gesellschaft. Zur Soziologie der Inneren Sicherheit, Hrsg., Opladen 2003, 472 S.
• Politische Steuerung und Reform der Landesverwaltung, Hrsg. (L. Kißler, N. Kersting und H.-J. Lange), Baden-Baden 2000, 171 S.
• Staat, Demokratie und Innere Sicherheit in Deutschland, Hrsg., Opladen 2000, 436 S.
• Innere Sicherheit im Politischen System der Bundesrepublik Deutschland, Opladen 1999, 478 S.
• Responsivität und Organisation. Eine Studie über die Modernisierung der CDU von 1973-89, Marburg 1994, 584 S.
• Computer in Parteien und Verbänden (zus. mit J. Bogumil), Opladen 1991, 245 S.
• Bonn am Draht. Politische Herrschaft in der technisierten Demokratie, Marburg 1988, 181 S.

Moreover papers, articles and presentations on the above-mentioned research issues.