Until recently, few enterprises were using open source software for back office applications, such as enterprise resource planning (ERP) and customer relationship management (CRM). But last month, an IDC survey of Western European companies found that nearly ten percent were using open source enterprise software. That's surprisingly high for a market where the industry leaders themselves have only a ten percent share. IDC also reported that the leading open source enterprise applications are growing - by 20 percent or more per year.

That's good news for the owners of the projects on our list. Unlike other categories of open-source applications, a high percentage of enterprise projects are money-making ventures that offer commercial support, training, and/or add-on features.

The scent of money in the air probably also explains why there are so many open source enterprise applications available. In other categories, like open source browsers, for instance, you'll struggle to find half a dozen good choices. But if you're looking for open source CRM or content management apps, you'll face more of a struggle in narrowing the dozens of choices down to a short list.

To help you get started on the process, here are 101 open source enterprise applications.

Note: Enterprise applications can be very difficult to categorize. The features that one group calls "customer relationship management," another group may call "sales force automation." And terms like "content management" and "groupware" mean very different things to different people.

In addition, many of these apps combine multiple functions in a single package. For the purposes of this list, we tried to categorize applications as they described themselves. Applications that didn't fit neatly into a single category ended up in the "Business Suites" category.

Accounting

1. FrontAccounting

This Web-based accounting/ERP app handles purchase orders, invoices, accounts payable, inventory, sales orders, general ledger, and more. In addition, it supports multiple languages, multiple currencies, and multiple GST/VAT settings. Operating System: Windows, Linux. Commercial Support Available? No, but a list of partners is available.

2. osFinancials

osFinancials includes accounting, invoicing, stock control, and POS abilities. It supports multiple users, up to 1 million debtors and creditors, and up to 1 million stock items. Operating System: Windows, Linux, Unix. Commercial Support Available? Yes

3. FriFinans

An alternative to Web-based open-source accounting apps, FriFinans is a cross-platform, multi-user, client/server finance system. It tracks accounts, offers, orders, invoices, purchase orders, payments, etc. and generates pdf reports of activities. Operating System: Windows, Linux. Commercial Support Available? No

Business Intelligence (BI)

4. Pentaho

The Pentaho Business Intelligence suite includes modules for reporting, analysis, data integration, dashboards, and data mining that can be deployed together or independently. Users include U.S. Naval Air Systems Command, Lifetime Networks, Terra Industries, Sun Microsystems, and MySQL. Operating System: Windows, Linux, OS X. Commercial Support Available? Yes

5. JasperSoft

The creators of the "most widely used open source business intelligence" offer a host of BI products, including the comprehensive JasperSoft Business Intelligence Suite, JasperReports report development library, JasperServer query and reporting server, JasperAnalysis interactive OLAP analysis, and JasperETL high performance data integration. The fee-based professional versions add Web 2.0, ad hoc query, and dashboard design capabilities. Operating System: OS Independent. Commercial Support Available? Yes

6. OpenI

With OpenI, you can easily visualize data from OLAP and relational databases and create your own reports, analyses, and dashboards. Future versions will support data mining models and Web data sources. Operating System: OS Independent. Commercial Support Available? No

7. Palo BI Suite

The Palo BI Suite includes three separate modules: Palo OLAP server for multi-user collaboration on BI data and analysis, Palo Worksheet Server for online spreadsheets with advance reporting capabilities, and Palo ETL server which extracts, transforms, and loads data from various sources. It's available in both the free community edition and the supported commercial edition. Operating System: OS Independent. Commercial Support Available? Yes

8. RapidMiner

Calling itself "the world-wide leading open-source data mining solution," RapidMiner includes more than 400 data mining operators that can be used independently or combined. The fee-based enterprise editions add other business intelligence capabilities, as well as support and warranties. Operating System: OS Independent. Commercial Support Available? Yes

9. OpenReports

This Web reporting solution generates dynamic reports from any browser and supports JasperReports, JFreeReport, JXLS, Eclipse BIRT, and OLAP. The fee-based professional version adds dashboards, alerts, and conditional report scheduling. Operating System: OS Independent. Commercial Support Available? Yes

10. Mondrian

From the makers of Pentaho, Mondrian is a Java-based OLAP engine. That means you can use it to analyze large SQL databases without knowing how to write SQL. Operating System: OS Independent. Commercial Support Available? Yes

11. JMagallanes

This reporting tool can be used to create static reports, swing pivot tables for OLAP analysis, and charts. It reads SQL, Excel, and XML data and exports to PDF and Excel files. Operating System: OS Independent. Commercial Support Available? Yes

Business Process Management/Business Performance Management (BPM)

12. ProcessMaker

Aimed at small-to-medium enterprises or strategic business units within a larger organization, ProcessMaker makes it easy for business managers with no programming experience to create models of business processes. It's Web-based and connects easily with existing ERP, BI, DMS, and CRM applications. Operating System: Windows, Linux. Commercial Support Available? Yes

13. Intalio BPMS

Used by more than 50,000 organizations, Intalio is one of the world's most popular business process management systems. Note that while Intalio has made much of the code available under an open-source license, they consider the free community edition to be 80% open-source; 100% of the code is available for users who purchase the enterprise edition. Operating System: Windows, Linux, OS X. Commercial Support Available? Yes

14. uEngine

The uEngine BPM suite includes three separate components: BPM Foundation with a process engine and modeling tool; the process portal with personalization, single sign-on, and dashboard capabilities; and the BP Analyzer with OLAP analyzing and charting abilities. It supports multiple languages, including English, but because it is developed by a Korean company, parts of the Web site and interface sound strange to native English speakers. Operating System: OS Independent. Commercial Support Available? Yes, but only in Korean

15. Adaptive Planning

Designed to replace spreadsheet-based processes, Adaptive Planning includes budgeting, forecasting, and reporting capabilities. In addition to the free Express version, it's also available in commercial Corporate and Enterprise editions that can be deployed on-demand (hosted) or on-premise. Operating System: Windows, Linux. Commercial Support Available? Yes

Business Suites

16. ADempiere ERP Business Suite

ADempiere combines ERP, CRM, and supply chain management functionality into a single package that is similar to Compiere but managed by a community instead of a company. You can try it out for yourself through the Online Demo. Operating System: Windows, Linux, Unix, OS X, BSD, Solaris. Commercial Support Available? Yes, through ADempiere Business Services

17. Compiere ERP + CRM Business Solution

Compiere aims to make ERP and CRM easier to acquire, implement, extend, and change. In addition to the free Community Edition, Compiere is available in a Standard Edition (open source with support and upgrades), Professional Edition (commercial license), or a Cloud Edition (commercial license, deployed through Amazon EC2). Operating System: Windows, Linux, Unix, OS X, BSD, Solaris. Commercial Support Available? Yes

18. opentaps

Short for "OPen source ENTerprise APplications Suite," opentaps combines ERP and CRM in a single integrated suite. Modules include inventory/shipping/warehouse, online store, CRM/order entry/marketing, POS, parties & users, AR/AP ledger, purchasing/planning, and product catalog. Operating System: Windows, Linux, Unix. Commercial Support Available? Yes

19. Plazma ERP + CRM

The Plazma Business Solution is primarily a CRM app with some ERP features. It manages accounts, contacts, sales, tasks, campaigns, and products and creates analytical reports. Operating System: Windows, Linux, OS X. Commercial Support Available? No

20. JAllInOne ERP/CRM

Despite its name, JAllInOne is primarily an ERP solution with some basic CRM functions. It provides all the standard ERP functionality and supports multiple users, multiple languages, and multiple companies. Operating System: OS Independent. Commercial Support Available? No

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