In my webapp I am trying to send emails only on errors, with everything else logged to a file. I am using logback under slf4j, with the log4j/slf4j bridge for the external libraries that normally use log4j. My configuration file is reloaded in the servlet context init (using the Joran configurator example from the documentation) so I can set some system properties used in the appenders (like the context name). The logging config has : <root level="ERROR"> <appender-ref ref="EMAIL" /> <appender-ref ref="FILE" /> </root> <logger name="foo" level="DEBUG"> <appender-ref ref="FILE" /> </logger> *Everything* not of log level ERROR coming from foo is getting logged twice. Why? I've pored over Chapter 2 of the documentation and it seems to describe the opposite of what is happening. The level for foo will ideally swap between DEBUG and INFO, but I can't have things logged twice all the time. How do I fix this? Thanks Chris