JKP Application Development Services was founded in November 2003 by me, Jan Karel Pieterse (owner).
JKP Application Development Services develops custom-made applications, using Microsoft Office Excel® and VBA and Access and VBA to their full extent. Other Office applications are integrated into the solutions where needed.
Training programs are also possible; We offer both pre-scheduled trainings and custom-made courses. Content of trainings can be adapted to your needs. If preferred we also offer any course as an in-house training.
My Services page shows you what services I can provide. This page also includes a list of recent projects so you can assess my level of experience in the business.
My Products page shows some samples of products I have developed.
About Jan Karel
I have been supporting Microsoft Excel users from over the world for many years, helping them with their day-to-day tasks using Microsoft Excel.
These efforts have been rewarded by Microsoft by granting me the MVP Award many times (each year starting from 2002). Worldwide, there are only about 100 Excel MVP's, so with JKP Application Development Services you are sure to get top level expertise. Get a real Excel expert to help you!
As a process engineer with about 20 years of corporate experience, I have experience in business processes as well as knowledge of the systems used for those processes.
Practical VBA implementations, Excel Experts Class 2015, 11 Dec 2015, Bunnik
Using Styles in Excel, Excel Experts Class 2015, 11 Dec 2015, Bunnik
Excel On-line, Excel Experience day 2015, 10 Dec 2015, Arnhem
VBA without programming, Excel Experience day 2015, 10 Dec 2015, Arnhem
Working with Circular References in Excel, Modeloff Global Training Camp, London, 4 December 2015
Speading up your reports, Excel Experts Class 2014, 12 december 2014
Importing data, Excel Experts Class 2014, 12 december 2014
Live demo: Building an application in VBA, Excel Experience day 2014, 11 december 2014, Arnhem
Building an All-VBA treeview control, Excel MVP Meeting Europe, May 26, 2014, Schiphol
From Model to Application, Excel Experts Class 2013, december 13, 2013, Bunnik
The Range Object, Excel Experts Class 2013, december 13, 2013, Bunnik
VBA Demonstration, Excel Experience Day 2013, december 12, 2013, Bunnik
Speed up your spreadsheet, Excel Experience Day 2013, december 12, 2013, Bunnik
An introduction to VBA, The European Investment Bank, September 5, 2013, Luxemburg
Pivot tables from start to finish, Excel Experts Class 2012, December 14, 2012, Amsterdam
VBA: introduction to userforms, Excel Experts Class 2012, December 14, 2012, Amsterdam
Excel 2013; the next generation, Excel Experience day 2012, December 13, 2012, Ede
Hidden problems in Excel files; How to keep your spreadsheets healthy. Excel Experience day 2012, December 13, 2012, Ede
Pivot tables en Slicers, ISA Group Excel training, 10 February 2012, Utrecht
Getting (external) data into Excel , Excel Experts Class 2011, December 9, 2011, Utrecht
Advanced userforms, Excel Experts Class 2011, December 9, 2011, Utrecht
VBA: working with variables, Excel Experience day 2011, December 8, 2011, Ede
Using Userforms in VBA-macro's, Excel Experience Day 2011, December 8, 2011, Ede
Distributing VBA Macro’s to other users, Excel Experts Class 2010, December 10, 2010, Amsterdam
Introduction to Excel VBA, Excel Experience Day 2010, December 9, 2010, Ede
Presentation at the Microsoft Global MVP Summit at Redmond. Presenting to the Microsoft Office Excel product group. Content and title under NDA. February 16, 2010. Redmond WA, USA.
Practical applications with VBA. Excel Experience Day 2009, December 10, 2009. Ede, The Netherlands.
Using Pivot Tables. Excel Experience Day 2008, December 11, 2008. Ede, The Netherlands.
Introduction to Excel VBA. Excel Experience Day 2008. December 11, 2008. Ede, The Netherlands.
Avoid mistakes, pitfalls in using Excel. Excel Experience Day 2007. December 11, 2007. Ede, The Netherlands.
Introduction to Excel VBA. Excel Experience Day 2007. December 11, 2007. Ede, The Netherlands.
Excel Masterclass. "Nationale Office dag". November 30, 2006 Ede Netherlands.
Excel and XML, an Introduction, "Excel experience day 2006". December 7, 2006. Ede, The Netherlands.
Excel 12, "Nationale Office dag". November 29, 2005. Ede, The Netherlands.
Revision author of Excel 2007 VBA Programming for Dummies. Author: John Walkenbach, publisher: Wiley. ISBN: 978-0-470-04674-6.
Dutch Article: Excel 12 is in aantocht!, Microsoft Office magazine (number 29, Spring 2006)
Dutch Article: XML breekt door, Microsoft Office magazine (number 27,
You can read this article (in Dutch) here too.
Dutch article: Excel-macro's geschikt maken voor anderen., Microsoft Office magazine (number 25, April 2005 and number 26, July 2005). See this page for an English version of this article.
Dutch article: Bereiknamen in Excel, Microsoft Office magazine issue number 21, 2004.
Importing Text Files in an Excel Sheet, Microsoft blog, June 10, 2010
Where to Find the Form Controls Microsoft blog, February 13, 2010
Preventing auto_open and Workbook_Open events from running Microsoft blog, December 15, 2009
Using parameters with web queries, Microsoft MSDN article, August 2009
Editing Data in an Excel 2007 Open XML File with VBA, Microsoft, June 2009
Using Styles to Dress Up Your Worksheets in Excel 2007, Microsoft MSDN, March 2009
Fixing Links To UDFs in Add-ins, Microsoft Office Online, December 2008
Working with Tables in Excel 2007 (VBA), Microsoft Office Online, September 2008
Werken met tabellen in Excel 2007 (Dutch), Microsoft voor ondernemers website, September 2007
Microsoft Knowledge base
Macro in Excel Stops After A Workbook.Open Command, February 26, 2005
Method to Delete Corrupt Defined Names in Excel, June 2, 2004
If you have a remark or a question, or would like a quotation, please
use the form on my contact page or
send me an e-mail.
I invite you to browse through this site. Come back often, as I add information to it regularly.
Memberships and affiliates
I am member of the Dutch Excel Experts Nederland group, a team of independent Excel experts which have joined their forces to enable better service levels for their customers.