OJS vs OMP vs OPS: Choosing the Right PKP

The Public Knowledge Project (PKP) offers three distinct platforms for scholarly publishing: Open Journal Systems (OJS), Open Monograph Press (OMP), and Open Preprint Systems (OPS). Each serves different publishing needs, and choosing the right one depends on what you're actually trying to accomplish. Here's how they differ and how to decide which fits your situation.

Understanding PKP's Platform Family #

PKP develops open-source software supporting scholarly communication. Founded at the University of British Columbia, the project has become the backbone of academic publishing infrastructure worldwide. Their platforms share common code foundations, design philosophies, and the commitment to open access—but each addresses distinct publishing workflows.

Importantly, these platforms can work together. A university might run OJS for its journals, OMP for scholarly book publishing, and OPS for preprint services—all sharing infrastructure and administrative approaches while serving different publication types.

Open Journal Systems (OJS) #

OJS is PKP's flagship product and the world's most widely used journal management and publishing platform. Over 25,000 journals globally run on OJS, from small society publications to major academic institutions.

What OJS Handles #

OJS manages the complete journal publishing workflow: submission intake, peer review coordination, editorial decision-making, copyediting, production, and publication. It handles issue-based publication (traditional volume/issue structure), continuous publication, and various hybrid approaches.

The platform supports multiple journals from a single installation, making it efficient for institutions publishing several titles. Role-based permissions allow different editorial teams to manage their journals independently while sharing technical infrastructure.

When to Choose OJS #

OJS is appropriate when you're publishing serialised scholarly content—articles appearing in regular issues or continuous streams. This includes traditional academic journals, conference proceedings published as journal issues, and any periodical scholarly publication.

If your content fits the article model—discrete pieces with individual authors, peer review for each submission, and ongoing publication over time—OJS provides the workflow support you need.

Open Monograph Press (OMP) #

OMP addresses scholarly book publishing—a fundamentally different workflow than journal articles. While both involve peer review and editorial processes, books require different structures, review approaches, and production considerations.

What OMP Handles #

OMP manages monograph and edited volume workflows: proposal submission, series management, chapter-level organisation, multiple file formats (PDF, EPUB, HTML), and catalogue-based presentation rather than issue-based.

The platform supports both single-author monographs and edited collections with multiple contributors. It handles the extended timelines typical of book publishing and the complex rights and permissions issues that book projects involve.

When to Choose OMP #

Choose OMP when publishing book-length scholarly works: monographs, edited volumes, textbooks, or similar extended treatments. University presses, scholarly societies publishing book series, and institutional publishing programs find OMP suited to their needs.

If your publication involves chapters rather than articles, book-length rather than article-length content, and catalogue-style rather than issue-style presentation, OMP is the appropriate choice.

Open Preprint Systems (OPS) #

OPS is PKP's newest platform, addressing the growing preprint movement in scholarly communication. Preprints—manuscripts shared before peer review—serve different purposes than peer-reviewed publications and require different workflows.

What OPS Handles #

OPS provides rapid posting of scholarly manuscripts with minimal editorial intervention. Unlike OJS, which manages extensive peer review workflows, OPS focuses on quick screening and public sharing. Authors retain control of their work, can update versions, and typically link preprints to eventual peer-reviewed publications.

The platform handles DOI registration for preprints, version management as manuscripts evolve, and metadata for discoverability—without the extended editorial processes of traditional journal publishing.

When to Choose OPS #

OPS suits organisations wanting to host preprint servers: discipline-specific preprint archives, institutional preprint services, or community preprint platforms. It's appropriate when the goal is rapid dissemination rather than certification through peer review.

If your objective is speed-to-publication with author-controlled content rather than editorial gatekeeping, OPS provides the streamlined workflow you need.

Key Differences Compared #

Editorial Workflow Complexity #

OJS: Full peer review workflow with multiple stages, reviewer assignment, decision tracking, revisions, and editorial correspondence. Designed for thorough evaluation before publication.

OMP: Extended workflow accommodating book-length projects, proposal evaluation, chapter management, and longer timelines. Review processes adapt to book publishing norms.

OPS: Minimal workflow—primarily screening for appropriateness rather than quality evaluation. Designed for quick posting with author control.

Content Organisation #

OJS: Issues and articles. Content organised into volumes, issues, and individual articles. Supports continuous publication within this structure.

OMP: Catalogues and books. Content organised as individual titles with chapters, presented in catalogue format rather than issue format.

OPS: Subject areas and preprints. Flat organisation by discipline or topic without periodical structure.

Publication Speed #

OJS: Weeks to months, depending on peer review depth and editorial processes.

OMP: Months to years, reflecting book publishing realities.

OPS: Days or less, with minimal screening before posting.

Hybrid Scenarios #

Some organisations use multiple PKP platforms together:

Journal Plus Preprints: An OJS journal might encourage authors to post preprints on an affiliated OPS server before submission. This provides early dissemination while maintaining peer review for the journal version.

Institutional Publishing Programs: Universities might run OJS for faculty journals, OMP for university press books, and OPS for campus-wide preprint services—all from a coordinated publishing infrastructure.

Society Publishing: A scholarly society might use OJS for its peer-reviewed journal and OMP for occasional monograph series or conference proceedings volumes.

Technical Considerations #

All three platforms share technical foundations: PHP-based, MySQL/PostgreSQL databases, similar hosting requirements, and common administrative approaches. Skills developed managing one platform transfer to others. Plugin ecosystems overlap, though platform-specific plugins exist.

However, each platform has distinct configuration needs, workflow assumptions, and user interface elements. Expertise in OJS doesn't automatically mean expertise in OMP or OPS—familiarity with shared architecture still requires learning platform-specific elements.

Making the Decision #

The choice usually becomes clear when you define what you're publishing:

Publishing articles in a peer-reviewed journal? → OJS

Publishing scholarly books or edited volumes? → OMP

Hosting preprints for rapid sharing before peer review? → OPS

If your publishing program spans multiple types, you might need multiple platforms—which PKP's ecosystem accommodates well.

Getting Started #

PKP provides documentation, community forums, and demonstration installations for all platforms. Exploring these resources helps clarify which platform suits your needs before committing to implementation.

For most academic publishers in India and globally, OJS remains the primary need—journal publishing dominates scholarly communication. OMP serves the smaller but important scholarly book publishing community. OPS addresses the emerging preprint space that's particularly active in certain disciplines.