This article answers the question "How to become a proficient BizTalk Server professional?"

You will need training and preferably a good mentor. What would be a good starting point?  
There is such an overwhelming amount of resources available currently on the internet.
Where to start?
The Microsoft BizTalk Server website or the BizTalk Developer Center or the TechNet Wiki BizTalk resources entry page are good starting points.  Just reading these resources is only the start though.

The path to success

A successful learning path for BizTalk Server depends on:
  • A good mentor or teacher if one is available (Note that you might not have access to one or due to limitation in resources or budget).
  • Knowledge of .NET and Visual Studio (BizTalk artifacts).
  • Knowledge of SQL Server since BizTalk depends on SQL Server (see BizTalk Architecture picture below).
  • Knowledge of Windows Azure Platform (Windows Azure Service Bus).
  • Time and money, a good training from experienced professionals can speed up the process of learning BizTalk. Spend time to build up routine and experience.

BizTalk Architecture

A key concept you will need to learn and understand is the pub/sub architecture. At its core BizTalk is an event-processing engine  based on this architecture. Wikipedia describes this architecture as follows:

(or pub/sub) is a
messaging paradigm where senders (publishers) of messages are not programmed to send their messages to specific receivers (subscribers). Rather, published messages are characterized into classes, without knowledge of what (if any) subscribers there may be. Subscribers express interest in one or more classes, and only receive messages that are of interest, without knowledge of what (if any) publishers there are. This decoupling of publishers and subscribers can allow for greater scalability and a more dynamic network topology."

A good mentor or trainer

A good investment and to speed up the process of learning BizTalk is a good mentor or trainer. You will still need "flying hours" to build up routine and experience. A good mentor can be a senior and experienced colleague you work with or a trainer during a classroom training (see Invest time and money).

Knowledge of .NET and Visual Studio

Development for BizTalk Server is done through Visual Studio 2013. Visual Studio has templates for BizTalk artefacts like orchestration, pipelines, schemas and maps, so a BizTalk solution can be created (design time) and deployed to the BizTalk runtime. Besides artefacts .NET development can be done in creating pipeline components, custom functoids, custom adapters, and .NET helper classes to aid in orchestrations. As a BizTalk professional Visual Studio is your friend and required to build BizTalk solutions.

Knowledge of SQL Server

BizTalk Server depends on SQL Server and Microsoft BizTalk Server databases and their health is very important for a successful BizTalk Server messaging environment. How to achieve this is explained in How to maintain and troubleshoot BizTalk Server databases and if you review that article it will become obvious to you that you will need SQL Server knowledge.

Knowledge of Windows Azure Platform (Windows Azure Service Bus)

The Windows Azure Service Bus is a hosted, secure, and widely available infrastructure for widespread communication, large-scale event distribution, naming, and service publishing. What would the best place be to learn more about this technology? The Windows Azure Service Bus Resources, which is an excellent entry point to get access to some of the many community resources for the Windows Azure Service Bus. Studying the service bus can be another challenge next to BizTalk yet with the new cloud capabilities with BizTalk Server 2013 R2 you will need to (see BizTalk Server 2013: Connect to Azure Service Bus).

ESB Toolkit

It is possible that after gaining experience- and building/strengthen your knowledge in BizTalk you want to take it a step further by learning the ESB Toolkit. If you have your BizTalk environment available you can download and then install and configure ESB Toolkit 2.2 (Version 2.2 is target for new BizTalk 2013/R2). For reading you can start with a white paper by Jon Flanders.

Invest time and money

When you start learning BizTalk you will need to invest in time and get hold of some budget to get training, books (Amazon, see list here), software (MSDN Subscription) and hardware (you need at least a laptop/desktop with enough memory, disk and processor power). Learning can be done at a local training facility or you can go to Quicklearn and Pluralsight. If you do not have enough resources as in software/hardware you still can learn/experience BizTalk through.

Call for Action

I have explained the success factors for a successful learning path for BizTalk and if you have the necessary prerequisites as in software and a machine (laptop/desktop) you can start cracking. Best way to proceed is to build your own BizTalk environment with the online Installation Guide in your hand (latest version 2013/R2). You can also opt to run BizTalk Server VM in Windows Azure (see for instance Provisioning BizTalk Server 2013 R2 environment on Microsoft Azure IaaS Platform).

A BizTalk development environment can best be installed and configured on a VMWare or Hyper-V or in case you have enough budget and Microsoft Azure account use and VM in Azure. As soon as you have your environment available, download the BizTalk help file and follow the tutorials described in there (which can be viewed online). Through self-study you setup your own environment, do tutorials, try virtual labs and read books. If that is not enough you can get training:

QuickLearn offers BizTalk training classes and Pluralsight also offers BizTalk training classes ranging from introductory to advanced. If you're just getting started, you might want to check out their self-paced BizTalk Developer Fundamentals class. Finally, visit QuickLearn's Technical Library for resources and articles on BizTalk.

Besides that, there are several good resources available online:

See Also

Read suggested related topics: Another important place to find an extensive amount of BizTalk related articles is the TechNet Wiki itself. The best entry point is BizTalk Server Resources on the TechNet Wiki.