diff --git a/R/json.R b/R/json.R
index bc47de2..6e2296a 100644
--- a/R/json.R
+++ b/R/json.R
@@ -277,6 +277,14 @@ setMethod("toJSON", "list",
                  paste(sprintf("[%s", collapse), paste(els, collapse = sprintf(",%s", collapse)), sprintf("%s]", collapse))
            })
 
+setMethod("toJSON", "data.frame",
+           function(x, container = isContainer(x, asIs, .level), collapse = "\n", ..., .level = 1L, .withNames = length(x) > 0 && length(names(x)) > 0, .na = "null", .escapeEscapes = TRUE, pretty = FALSE, asIs = NA) {
+             # Data frame columns should always be treated as containers
+             toJSON(lapply(as.list(x), function(col) {
+               I(col)
+             }), container = container, collapse = collapse, ..., .level = .level, .withNames = .withNames, .na = .na, .escapeEscapes = .escapeEscapes, pretty = pretty, asIs = asIs)
+           })
+
 
 jsonPretty =
 function(txt)
diff --git a/man/toJSON.Rd b/man/toJSON.Rd
index 1aee176..d8ef501 100644
--- a/man/toJSON.Rd
+++ b/man/toJSON.Rd
@@ -2,6 +2,8 @@
 \alias{toJSON}
 \alias{toJSON,list-method}
 \alias{toJSON,ANY-method}
+\alias{toJSON,array-method}
+\alias{toJSON,function-method}
 \alias{toJSON,numeric-method}
 \alias{toJSON,integer-method}
 \alias{toJSON,integer,missing-method}
@@ -11,7 +13,7 @@
 \alias{toJSON,matrix-method}
 \alias{toJSON,ANY-method}
 \alias{toJSON,name-method}
-\alias{toJSON,list-method}
+\alias{toJSON,data.frame-method}
 \alias{toJSON,NULL-method}
 \alias{toJSON,factor-method}
 \alias{toJSON,AsIs-method}