diff --git a/DESCRIPTION b/DESCRIPTION
index 99cf607d29..e244a932ad 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -254,6 +254,6 @@ Collate:
     'zxx.r'
     'zzz.r'
 VignetteBuilder: knitr
-RoxygenNote: 7.0.2
+RoxygenNote: 7.1.0
 Roxygen: list(markdown = TRUE)
 Encoding: UTF-8
diff --git a/NAMESPACE b/NAMESPACE
index efeddbb12d..8f74d21e39 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -107,6 +107,7 @@ S3method(makeContext,dotstackGrob)
 S3method(merge_element,default)
 S3method(merge_element,element)
 S3method(merge_element,element_blank)
+S3method(merge_element,list)
 S3method(plot,ggplot)
 S3method(predictdf,default)
 S3method(predictdf,glm)
diff --git a/R/layer.r b/R/layer.r
index 69abc5ec06..46741a1196 100644
--- a/R/layer.r
+++ b/R/layer.r
@@ -223,8 +223,7 @@ Layer <- ggproto("Layer", NULL,
     if (!is.null(self$geom_params$group)) {
       aesthetics[["group"]] <- self$aes_params$group
     }
-
-    scales_add_defaults(plot$scales, data, aesthetics, plot$plot_env)
+    scales_add_defaults(plot$scales, data, aesthetics, plot$plot_env, plot$theme)
 
     # Evaluate aesthetics
     env <- child_env(baseenv(), stage = stage)
@@ -320,7 +319,7 @@ Layer <- ggproto("Layer", NULL,
     stat_data <- new_data_frame(compact(stat_data))
 
     # Add any new scales, if needed
-    scales_add_defaults(plot$scales, data, new, plot$plot_env)
+    scales_add_defaults(plot$scales, data, new, plot$plot_env, plot$theme)
     # Transform the values, if the scale say it's ok
     # (see stat_spoke for one exception)
     if (self$stat$retransform) {
diff --git a/R/plot-build.r b/R/plot-build.r
index dcac060141..bf07c9945a 100644
--- a/R/plot-build.r
+++ b/R/plot-build.r
@@ -43,6 +43,8 @@ ggplot_build.ggplot <- function(plot) {
     }
     out
   }
+  ## Build full theme combining supplied elements and current defaults
+  plot$theme <- plot_theme(plot)
 
   # Allow all layers to make any final adjustments based
   # on raw input data and plot info
@@ -163,7 +165,7 @@ ggplot_gtable.ggplot_built <- function(data) {
   plot <- data$plot
   layout <- data$layout
   data <- data$data
-  theme <- plot_theme(plot)
+  theme <- plot$theme
 
   geom_grobs <- Map(function(l, d) l$draw_geom(d, layout), plot$layers, data)
   layout$setup_panel_guides(plot$guides, plot$layers, plot$mapping)
diff --git a/R/scale-type.R b/R/scale-type.R
index 34ccf69308..99dce37aab 100644
--- a/R/scale-type.R
+++ b/R/scale-type.R
@@ -1,4 +1,4 @@
-find_scale <- function(aes, x, env = parent.frame()) {
+find_scale <- function(aes, x, env = parent.frame(), theme = NULL) {
   # Inf is ambiguous; it can be used either with continuous scales or with
   # discrete scales, so just skip in the hope that we will have a better guess
   # with the other layers
@@ -8,11 +8,17 @@ find_scale <- function(aes, x, env = parent.frame()) {
 
   type <- scale_type(x)
   candidates <- paste("scale", aes, type, sep = "_")
-
   for (scale in candidates) {
+    ## First try lookup in theme (if supplied)
+    default_scales <- calc_element("default.scales", theme)
+    scale <- default_scales[[name]]
+    if (!is.null(scale) && isTRUE(mode(scale) == mode)) {
+      return(scale)
+    }
     scale_f <- find_global(scale, env, mode = "function")
-    if (!is.null(scale_f))
+    if (!is.null(scale_f)) {
       return(scale_f())
+    }
   }
 
   # Failure to find a scale is not an error because some "aesthetics" don't
diff --git a/R/scales-.r b/R/scales-.r
index d56036e8cf..7e46b37b17 100644
--- a/R/scales-.r
+++ b/R/scales-.r
@@ -88,7 +88,7 @@ scales_transform_df <- function(scales, df) {
 
 # @param aesthetics A list of aesthetic-variable mappings. The name of each
 #   item is the aesthetic, and the value of each item is the variable in data.
-scales_add_defaults <- function(scales, data, aesthetics, env) {
+scales_add_defaults <- function(scales, data, aesthetics, env, theme) {
   if (is.null(aesthetics)) return()
   names(aesthetics) <- unlist(lapply(names(aesthetics), aes_to_scale))
 
@@ -100,7 +100,7 @@ scales_add_defaults <- function(scales, data, aesthetics, env) {
   datacols <- compact(datacols)
 
   for (aes in names(datacols)) {
-    scales$add(find_scale(aes, datacols[[aes]], env))
+    scales$add(find_scale(aes, datacols[[aes]], env, theme))
   }
 
 }
diff --git a/R/theme-elements.r b/R/theme-elements.r
index 68bc7661d9..6566d57a6d 100644
--- a/R/theme-elements.r
+++ b/R/theme-elements.r
@@ -480,6 +480,7 @@ el_def <- function(class = NULL, inherit = NULL, description = NULL) {
   strip.placement.y   = el_def("character", "strip.placement"),
   strip.switch.pad.grid = el_def("unit"),
   strip.switch.pad.wrap = el_def("unit"),
+  default.scales      = el_def("list"),
 
   plot.background     = el_def("element_rect", "rect"),
   plot.title          = el_def("element_text", "title"),
diff --git a/R/theme.r b/R/theme.r
index 7cf5556b89..afd5029d76 100644
--- a/R/theme.r
+++ b/R/theme.r
@@ -356,6 +356,7 @@ theme <- function(line,
                   strip.text.y,
                   strip.switch.pad.grid,
                   strip.switch.pad.wrap,
+                  default.scales,
                   ...,
                   complete = FALSE,
                   validate = TRUE
@@ -643,6 +644,14 @@ merge_element.element <- function(new, old) {
   new
 }
 
+#' @rdname merge_element
+#' @export
+merge_element.list <- function(new, old) {
+  overlap <- intersect(names(new), names(old))
+  old <- old[setdiff(names(old), overlap)]
+  append(old, new)
+}
+
 #' Combine the properties of two elements
 #'
 #' @param e1 An element object
diff --git a/man/diamonds.Rd b/man/diamonds.Rd
index ed13e7e846..7c3be09436 100644
--- a/man/diamonds.Rd
+++ b/man/diamonds.Rd
@@ -4,7 +4,8 @@
 \name{diamonds}
 \alias{diamonds}
 \title{Prices of over 50,000 round cut diamonds}
-\format{A data frame with 53940 rows and 10 variables:
+\format{
+A data frame with 53940 rows and 10 variables:
 \describe{
 \item{price}{price in US dollars (\$326--\$18,823)}
 \item{carat}{weight of the diamond (0.2--5.01)}
@@ -17,7 +18,8 @@ SI1, VS2, VS1, VVS2, VVS1, IF (best))}
 \item{z}{depth in mm (0--31.8)}
 \item{depth}{total depth percentage = z / mean(x, y) = 2 * z / (x + y) (43--79)}
 \item{table}{width of top of diamond relative to widest point (43--95)}
-}}
+}
+}
 \usage{
 diamonds
 }
diff --git a/man/economics.Rd b/man/economics.Rd
index e099d23e8e..d2fb819ba5 100644
--- a/man/economics.Rd
+++ b/man/economics.Rd
@@ -5,7 +5,8 @@
 \alias{economics}
 \alias{economics_long}
 \title{US economic time series}
-\format{A data frame with 574 rows and 6 variables:
+\format{
+A data frame with 574 rows and 6 variables:
 \describe{
 \item{date}{Month of data collection}
 \item{pce}{personal consumption expenditures, in billions of dollars,
@@ -18,7 +19,10 @@
 \url{http://research.stlouisfed.org/fred2/series/UEMPMED}}
 \item{unemploy}{number of unemployed in thousands,
 \url{http://research.stlouisfed.org/fred2/series/UNEMPLOY}}
-}}
+}
+
+An object of class \code{tbl_df} (inherits from \code{tbl}, \code{data.frame}) with 2870 rows and 4 columns.
+}
 \usage{
 economics
 
diff --git a/man/faithfuld.Rd b/man/faithfuld.Rd
index a5d8d0b7d0..5f8e0c32e9 100644
--- a/man/faithfuld.Rd
+++ b/man/faithfuld.Rd
@@ -4,12 +4,14 @@
 \name{faithfuld}
 \alias{faithfuld}
 \title{2d density estimate of Old Faithful data}
-\format{A data frame with 5,625 observations and 3 variables:
+\format{
+A data frame with 5,625 observations and 3 variables:
 \describe{
 \item{eruptions}{Eruption time in mins}
 \item{waiting}{Waiting time to next eruption in mins}
 \item{density}{2d density estimate}
-}}
+}
+}
 \usage{
 faithfuld
 }
diff --git a/man/ggplot2-package.Rd b/man/ggplot2-package.Rd
index 0eee1459e6..2f427a1f53 100644
--- a/man/ggplot2-package.Rd
+++ b/man/ggplot2-package.Rd
@@ -39,7 +39,7 @@ Authors:
 
 Other contributors:
 \itemize{
-  \item RStudio [copyright holder]
+  \item RStudio [copyright holder, funder]
 }
 
 }
diff --git a/man/graphical-units.Rd b/man/graphical-units.Rd
index 1822d48011..ffd13a79a3 100644
--- a/man/graphical-units.Rd
+++ b/man/graphical-units.Rd
@@ -5,7 +5,11 @@
 \alias{.pt}
 \alias{.stroke}
 \title{Graphical units}
-\format{An object of class \code{numeric} of length 1.}
+\format{
+An object of class \code{numeric} of length 1.
+
+An object of class \code{numeric} of length 1.
+}
 \usage{
 .pt
 
diff --git a/man/luv_colours.Rd b/man/luv_colours.Rd
index fedeb3dcef..5985911f99 100644
--- a/man/luv_colours.Rd
+++ b/man/luv_colours.Rd
@@ -4,11 +4,13 @@
 \name{luv_colours}
 \alias{luv_colours}
 \title{\code{colors()} in Luv space}
-\format{A data frame with 657 observations and 4 variables:
+\format{
+A data frame with 657 observations and 4 variables:
 \describe{
 \item{L,u,v}{Position in Luv colour space}
 \item{col}{Colour name}
-}}
+}
+}
 \usage{
 luv_colours
 }
diff --git a/man/merge_element.Rd b/man/merge_element.Rd
index 913e75ce73..760a3467af 100644
--- a/man/merge_element.Rd
+++ b/man/merge_element.Rd
@@ -5,6 +5,7 @@
 \alias{merge_element.default}
 \alias{merge_element.element_blank}
 \alias{merge_element.element}
+\alias{merge_element.list}
 \title{Merge a parent element into a child element}
 \usage{
 merge_element(new, old)
@@ -14,6 +15,8 @@ merge_element(new, old)
 \method{merge_element}{element_blank}(new, old)
 
 \method{merge_element}{element}(new, old)
+
+\method{merge_element}{list}(new, old)
 }
 \arguments{
 \item{new}{The child element in the theme hierarchy}
diff --git a/man/midwest.Rd b/man/midwest.Rd
index ee8b5e85ae..4998fa6192 100644
--- a/man/midwest.Rd
+++ b/man/midwest.Rd
@@ -4,7 +4,8 @@
 \name{midwest}
 \alias{midwest}
 \title{Midwest demographics}
-\format{A data frame with 437 rows and 28 variables:
+\format{
+A data frame with 437 rows and 28 variables:
 \describe{
 \item{PID}{}
 \item{county}{}
@@ -34,7 +35,8 @@
 \item{percelderlypoverty}{}
 \item{inmetro}{In a metro area.}
 \item{category}{}
-}}
+}
+}
 \usage{
 midwest
 }
diff --git a/man/mpg.Rd b/man/mpg.Rd
index ec696861bd..a855a6c632 100644
--- a/man/mpg.Rd
+++ b/man/mpg.Rd
@@ -4,7 +4,8 @@
 \name{mpg}
 \alias{mpg}
 \title{Fuel economy data from 1999 to 2008 for 38 popular models of cars}
-\format{A data frame with 234 rows and 11 variables:
+\format{
+A data frame with 234 rows and 11 variables:
 \describe{
 \item{manufacturer}{manufacturer name}
 \item{model}{model name}
@@ -17,7 +18,8 @@
 \item{hwy}{highway miles per gallon}
 \item{fl}{fuel type}
 \item{class}{"type" of car}
-}}
+}
+}
 \usage{
 mpg
 }
diff --git a/man/msleep.Rd b/man/msleep.Rd
index a53c1cd3e2..5e513a0b87 100644
--- a/man/msleep.Rd
+++ b/man/msleep.Rd
@@ -4,7 +4,8 @@
 \name{msleep}
 \alias{msleep}
 \title{An updated and expanded version of the mammals sleep dataset}
-\format{A data frame with 83 rows and 11 variables:
+\format{
+A data frame with 83 rows and 11 variables:
 \describe{
 \item{name}{common name}
 \item{genus}{}
@@ -17,7 +18,8 @@
 \item{awake}{amount of time spent awake, in hours}
 \item{brainwt}{brain weight in kilograms}
 \item{bodywt}{body weight in kilograms}
-}}
+}
+}
 \usage{
 msleep
 }
diff --git a/man/presidential.Rd b/man/presidential.Rd
index 4c827f93aa..71b7b16ffe 100644
--- a/man/presidential.Rd
+++ b/man/presidential.Rd
@@ -4,13 +4,15 @@
 \name{presidential}
 \alias{presidential}
 \title{Terms of 11 presidents from Eisenhower to Obama}
-\format{A data frame with 11 rows and 4 variables:
+\format{
+A data frame with 11 rows and 4 variables:
 \describe{
 \item{name}{Last name of president}
 \item{start}{Presidency start date}
 \item{end}{Presidency end date}
 \item{party}{Party of president}
-}}
+}
+}
 \usage{
 presidential
 }
diff --git a/man/scale_discrete.Rd b/man/scale_discrete.Rd
index e5e323adae..c4bf774d42 100644
--- a/man/scale_discrete.Rd
+++ b/man/scale_discrete.Rd
@@ -32,8 +32,8 @@ The default, \code{TRUE}, uses the levels that appear in the data;
     \item{\code{na.translate}}{Unlike continuous scales, discrete scales can easily show
 missing values, and do so by default. If you want to remove missing values
 from a discrete scale, specify \code{na.translate = FALSE}.}
-    \item{\code{na.value}}{If \code{na.translate = TRUE}, what value aesthetic
-value should missing be displayed as? Does not apply to position scales
+    \item{\code{na.value}}{If \code{na.translate = TRUE}, what aesthetic value should the
+missing values be displayed as? Does not apply to position scales
 where \code{NA} is always placed at the far right.}
     \item{\code{aesthetics}}{The names of the aesthetics that this scale works with.}
     \item{\code{scale_name}}{The name of the scale that should be used for error messages
diff --git a/man/scale_manual.Rd b/man/scale_manual.Rd
index dd4b943056..6fbefc58f7 100644
--- a/man/scale_manual.Rd
+++ b/man/scale_manual.Rd
@@ -40,8 +40,8 @@ The default, \code{TRUE}, uses the levels that appear in the data;
     \item{\code{na.translate}}{Unlike continuous scales, discrete scales can easily show
 missing values, and do so by default. If you want to remove missing values
 from a discrete scale, specify \code{na.translate = FALSE}.}
-    \item{\code{na.value}}{If \code{na.translate = TRUE}, what value aesthetic
-value should missing be displayed as? Does not apply to position scales
+    \item{\code{na.value}}{If \code{na.translate = TRUE}, what aesthetic value should the
+missing values be displayed as? Does not apply to position scales
 where \code{NA} is always placed at the far right.}
     \item{\code{scale_name}}{The name of the scale that should be used for error messages
 associated with this scale.}
diff --git a/man/scale_shape.Rd b/man/scale_shape.Rd
index 0c3ba1524c..aa557fa7d6 100644
--- a/man/scale_shape.Rd
+++ b/man/scale_shape.Rd
@@ -35,8 +35,8 @@ The default, \code{TRUE}, uses the levels that appear in the data;
     \item{\code{na.translate}}{Unlike continuous scales, discrete scales can easily show
 missing values, and do so by default. If you want to remove missing values
 from a discrete scale, specify \code{na.translate = FALSE}.}
-    \item{\code{na.value}}{If \code{na.translate = TRUE}, what value aesthetic
-value should missing be displayed as? Does not apply to position scales
+    \item{\code{na.value}}{If \code{na.translate = TRUE}, what aesthetic value should the
+missing values be displayed as? Does not apply to position scales
 where \code{NA} is always placed at the far right.}
     \item{\code{aesthetics}}{The names of the aesthetics that this scale works with.}
     \item{\code{scale_name}}{The name of the scale that should be used for error messages
diff --git a/man/seals.Rd b/man/seals.Rd
index a3a3cccdcb..4b364a6bf2 100644
--- a/man/seals.Rd
+++ b/man/seals.Rd
@@ -4,7 +4,9 @@
 \name{seals}
 \alias{seals}
 \title{Vector field of seal movements}
-\format{A data frame with 1155 rows and 4 variables}
+\format{
+A data frame with 1155 rows and 4 variables
+}
 \usage{
 seals
 }
diff --git a/man/theme.Rd b/man/theme.Rd
index 457cdb5f02..414103f42f 100644
--- a/man/theme.Rd
+++ b/man/theme.Rd
@@ -97,6 +97,7 @@ theme(
   strip.text.y,
   strip.switch.pad.grid,
   strip.switch.pad.wrap,
+  default.scales,
   ...,
   complete = FALSE,
   validate = TRUE
diff --git a/man/txhousing.Rd b/man/txhousing.Rd
index e9183ea37c..d983392ff8 100644
--- a/man/txhousing.Rd
+++ b/man/txhousing.Rd
@@ -4,7 +4,8 @@
 \name{txhousing}
 \alias{txhousing}
 \title{Housing sales in TX}
-\format{A data frame with 8602 observations and 9 variables:
+\format{
+A data frame with 8602 observations and 9 variables:
 \describe{
 \item{city}{Name of multiple listing service (MLS) area}
 \item{year,month,date}{Date}
@@ -14,7 +15,8 @@
 \item{listings}{Total active listings}
 \item{inventory}{"Months inventory": amount of time it would take to sell
 all current listings at current pace of sales.}
-}}
+}
+}
 \usage{
 txhousing
 }