Effective Web maps have a specific focus and are designed so users can interact with them to accomplish meaningful tasks. Five Steps to Better Performance Sample methodology for creating a great Web map By Bronwyn Agrios, Esri Education Services Optimized Map Service, a new map service type available beginning with ArcGIS 9.3.1, significantly boosts the performance of dynamic operational layers in Web maps. This article steps through a new recommended workflow for Web map design that takes advantage of the performance improvements in ArcGIS 9.3.1 and introduces the new Map Service Publishing toolbar. The sample workflow described in this article goes through the stages leading up to and including application development. The workflow is summarized in the following five steps: Step 1: Think about the application and its users. Step 2: Design maps for Web applications. Step 3: Tune maps to optimize request performance. Step 4: Save maps and publishing layers. Step 5: Visualize basemap and operational services in a Web application. These steps use publicly available data from the ArcGIS Online servers. Readers who have their own data and an installation of ArcGIS Desktop and ArcGIS Server with the permissions to create services can follow these steps. For more information on the application design process, see the ArcGIS Desktop help topic "Steps for implementing GIS map applications" located in the book GIS servers and services > Creating and publishing Web maps for ArcGIS Server. What data will be included in the application? How will the data be used? Visualization? Spatial query? Attribute query? Will the data be used with other services to create a mashup? Answering these questions will help narrow the focus of the application and develop maps and tools for specific tasks. These will also serve as a guide through the process of envisioning the project and will lead more quickly to a successful result. Step One Think about the application and its users As any good project manager knows, projects should be planned before they are started. Before developing a map-based Web application, spend some time thinking about the application users and how they can best be served by this application. Consider the following questions: What is the business need/purpose of the Web mapping application? Who are the end users? Is this an internal or external Web site? Step Two Design maps for Web applications Following best practices for Web map design, the maps used in this application will be divided into a single cached base layer and multiple operational layers, both cached and dynamic. All content should n Employ strong cartography. n Use scale dependency to enhance performance and improve clarity. n Maintain the identical coordinate systems for all map layers used in the application. 44 ArcUser Summer 2009 ArcUser Summer ArcUser Summer www.esri.com